Thanks for this informative video about the Sencore TC162 Tube Tester. I worked at Sencore for some six years, starting as a factory service technician. The TC162 was my favorite machine to work on, having tested TV and radio electron tubes at my Dad's store since I was ten years old. The Sencore approach was focused on the service technician determining quick "Good-?-Bad" testing, especially in home service calls, rather than complicated engineering parameters of Hickok and other testers, which I also used.
Alan, very nostalgic. As a kid in the 60's I remember the corner "candy" store, complete with soda fountain, had a tube testing console. Looking back, I find it remarkable that there were people "handy" enough to take the back off a tv or radio and pull some tubes for testing. Today, the legal liability alone would prohibit that. I enjoyed your Tek commercial before the vid as well, that is some piece of gear. Thanks, Dave
I remember the drug-store tube testers also. FYI - I have NO control over the commercials/ads that play before and during my videos. That's all determined by RUclips and Google, not me. So, I don't know what commercial you saw...
Great history/tutorial, thanks Alan. I'm privileged to own this unit's big brother, a Sencore Mu140, which partly addresses the gap between "test" and "real world" conditions. Besides shorts, leakage and emission, the Mu140 also measures transconductance; and unlike old-school Hickocks etc., does so with a 5 kHz audio test signal. It also uses an "auto grid bias" that simulates typical in-circuit biasing. Very hard for a weak tube to sneak by. Only annoyance is that (like the 162) the meter isn't graduated in uA/mA, just the stupid go/nogo bands.
I own all models of these Sencore Mighty Mights, including the TC162. Build quality of these units was state-of-the-art in their day. If you were a Radio &TV Repairman in 60s & 70s, you carried one in your truck for service calls. Good times.
HI Alan, great video on the subtleties of tube testing and its limitations. Brought back memories of my dad teaching me how to use one properly. One minor comment, the plate cap wire you mentioned can also be a grid cap as well for some tubes.
The TC 162 has the best grid leakage of any tube tester I have ever encountered; even my B&K 747 fails in this category. Yes! you are right about no tube tester can simulate the actual working condition. If I am not sure about the results, I will check it on a second tester to reduce false readings or substitute a replacement.
Next to radios this is my next weakness. Can never pass on buying another tube tester. Have all the big boy high end testers from AVO, Hickock, Tripplet, Westmore, B&K, Sencore and even have a custom laboratory tester that came out of a Westinghouse lab. My favorite is probably the Tripplet 3444 laboratory mutual conductance tester. One of the best portable testers ever made. For the average user the Sencore is a great little tester. It's one of the first testers I ever bought and tested thousands of tubes on It. Definitely one of the great emission testers.
That's a nice tester! I have one just like that. Out of curiosity, I looked into the "life test" function. When you slide the switch over, there is a one ohm resistor that goes on series to the filaments. Since emissions are usually not a problem with rectifier tubes, this will help determine the heater is wearing out. Your presentation is spot on as always!
I know it’s been a while, but I’m interested in this life switch function. I was thinking of incorporating it into another vintage tester I have (University TST). I have read that it’s best to reduce the filament voltage by about 10% for a life test. Will this 1 ohm resister do that across all the filaments in this circuit?
I have one of these and a Hickok. You can build your own calibration plug using a old tube base. This tester works about as well as an emission tester can be expected to.
I'm a little late to this party having only just found this video in my feed today, but I found it useful nonetheless. I'm in the process of refurbishing a B&K 607 Tube Tester, a direct competitor to the Sencore TC162. About the only difference between the two is that the BK607 does not have the TC162's Life Test switch. I was a bit disappointed that you declined to test the 6146 tube you showed. My Kenwood TS830s uses two of those tubes. I'm trying to learn as much as I can about the radio before I tackle a full restoration and alignment on it.
Hi Alan, Interesting video! Sencore made excellent test gear overt the years. I'm a long time user of the TV7 for testing older radio/TV/Audio tubes,. Only problem is, it doesn't test the later Compactrons. There's where the Sencore comes in handy. It's a nice portable service tester for quick emission checks. I repair pro audio gear, but also specialize in vintage vacuum tube electronics repair/restoration...tube radios, TV's, Hi-fi & guitar amplifiers, recording & broadcast studio equipment. 80% of my work is tubes, and the rest solid state. Your videos are well enjoyed by me and many of my colleagues. One of these days, I have to get my old Tek 475 scope working properly again (an old favorite). May need some advice on that project :) Keep the great videos coming.
Yes Alan Very good video and sure remember using tube test in the TV and Radio Shop, and yes good point is to wait few minutes to double check the tube if any changes happen .had a Hickok then .. &3's Alan
You are one of the best instructors I've seen.. Seriously.. Excellent.. I would love to see some videos where you walk us through some schematics and fully explain them and talk about the design decisions that go into such circuits.. Or have you thought about an electronics course, starting from basics and getting into design? Just some suggestions...
I have *several* videos where I walk through the design, schematics, etc. - both on some circuits I've designed as well as some production products. Here's a short list: Flexible Ramp Generator: ruclips.net/video/bVahBmsvirE/видео.html Sawtooth Waveform Generator: ruclips.net/video/ibnz5UjQ4u0/видео.html Cascode Amplifier: ruclips.net/video/Op_I3Ke7px0/видео.html 555 Monostable: ruclips.net/video/MbWc70ZzTlI/видео.html Basics of Gilbert Cell: ruclips.net/video/7nmmb0pqTU0/видео.html Basics of Differential Amplifiers: ruclips.net/video/mejPNuPAHBY/видео.html Diode Ring Mixers: ruclips.net/video/junuEwmQVQ8/видео.html Directional Coupler: ruclips.net/video/byF1FLdbUiA/видео.html Op Amp Basics: ruclips.net/video/K03Rom3Cs28/видео.html Op Amp Peak Detector: ruclips.net/video/Fn5kHhNRsz0/видео.html Op Amp Summing Amplifier: ruclips.net/video/juQtVIx1a8g/видео.html Common Emitter Amp gain and frequency response: ruclips.net/video/NizrzRKQqII/видео.html Common Emitter, Base and Collector amplifiers: ruclips.net/video/zXh5gMc6kyU/видео.html Vbe Multiplier: ruclips.net/video/Obh_PIC2qqo/видео.html AutoRanging Analog Voltmeter: ruclips.net/video/7OLGswQ7ICI/видео.html RC Servo fun: ruclips.net/video/iaGZOO33Z-o/видео.html Single Cell LED light: ruclips.net/video/qfgX93o8HzY/видео.html Unique Stair-step Generator: ruclips.net/video/Kqb5zcrgv7s/видео.html Simple Transistor Curve tracer using stair-step: ruclips.net/video/ZOLLoa2fH24/видео.html 5 Transistor ESR meter: ruclips.net/video/3fiUZZlveS0/видео.html Heathkit CW Transceiver walk-though: ruclips.net/video/rPM1vvGorTo/видео.html MFJ CW Transciever walk-though: ruclips.net/video/2QSwXv2RJzw/видео.html TenTec 1254 Shortwave Receiver walk-through: ruclips.net/video/dZNN5RnOdt8/видео.html S-meter upgrade to 1254 receiver: ruclips.net/video/5yhMOcpHS7Q/видео.html Wadley Loop receiver: ruclips.net/video/JvS9tBWAc1s/видео.html
Cool device! Reminds me of when I was a kid repairing old WW2 tube radios and none of the equipment had polarized plugs or grounding. One time I had accidentally plugged in the tester backwards which made the case hot. I can't remember what I was holding, but in one hand I had a soldering iron or telephone and with the other I touched the controls and that thing shocked the the living hell out of me (arm-to-arm across my chest too! thank goodness for being young, ha).
Still have an older Sencore, plus a WWII military Mutual Transconductance tester for which I made a bank of modern sockets with a set of a dozen slide switches (1P10T) to do the switching. You had to do some "hoop-jumping" to translate from the Tube Characteristics manual to settings on the tester, but it was all I could afford as a one-man electronics repair shop back in the early '70s. I quit TV repair when TVs went to using $100 swap-out modules instead of discrete component repairs. No way for a one-man shop to stock every board for every TV.
Nice video, whenever I see one of a tube tester video I get the urge to go and buy one, then I remember I only have one bit of gear that has tubes, a HealthKit it12.
Great presentation of equipment, that seems to never get old. The wiring inside of the tester is amazing. Don't those wires get brittle over time? Great show, thanks!
Reminds me of some Saturday mornings from my childhood at Radio Shack or the local Drugstore (Dart Drug I think was a predecessor to Target? 🤔 We had a 25" Magnivox that ate tubes like crazy
I've had and used one of these for years. It is a great Go NoGo tester while nit a Mutual Conductance tester it is a good piece of test equipment! WB4IVG Laurin
I remember my Dad working on TV sets for Sears, he would stick a tube on the tester and then thump the tube with his fingers to see whether the tube was noisy or not. A lot of times they were after warming up. To think these were in grocery stores and people who didn’t know anything about electronics were diagnosing their own sets. Tube sales were high:-)
Not just intermittent shorts; sometimes tubes would become "microphonic". Vibration would change the µ so that any chassis vibration could set up noise or even audio feedback. A tap while in circuit would cause a thump or damped ringing in the speaker. One of the tube manufacturers made a give-away item which was a pencil with a t-shaped assembly for the eraser. It made the pencil into a tube-tapping hammer with eraser faces. I haven't seen the one I had for half a century. I probably used it as a pencil until it got too short and tossed it. (Who could foresee collectables and eBay back in the day?) [A couple minutes later] LOL - Evidently somebody did. I see dozens of eraser-hammer pencils on eBay. Oddly I didn't see any from a tube manufacturer. Search eBay for [ pencil double eraser ] The perfect weight, the resilience of the cedar shaft, and the elasticity of the eraser made a pretty good tube tapper as I recall. I bet the erasers are hard as rocks by now. The downside of using a pencil around any high voltages was that concealed within the cedar shaft was a pretty good conductor - a stick of graphite. I now recall that this was why I tossed my tube-thumper. One ZAP did it for me.
thank you, used such (similar) device 60 years ago in a Radio-Shop , when I was young, had no money and had to test old tubes, which I found in broken radios. Hihihihi.
The Emissions Test is an in series current meter Ammeter measuring the current from cathode to plate? The LIFE Test is putting a Load/parallel resistance on the plate of the tube to ground?
I have a Hickok 533A. This is the model that uses a light bulb as a fuse to protect itself. I found gum wrapper wrapped around the base of the bulb to short out the bulb and bypass it. Not safe at all.
What are Novars, Nuvistors, Compactrons tubes used for and why aren't they used more often in electronic circuit designs? I think most tube testers will measure and test Novars, Nuvistors and Compactrons
Thank for another great video Alan. Very good point you mentioned about waiting on the leakage test. That is a trap for young players. I have one solid state tester, EMC model 215. Never use it much. After many years (mid 80's) I got my old HICKOK 800A back that I sold after closing the TV shop down. Thanks for sharing.
Hah! I had an EMC 213. Wish I still had it. I built it from a kit, wired up all those sockets... I rather liked that unit. Got two other testers now, one newer one and an older unit that has the sockets for the pre-WWII stuff.
When measure a vacuum tube amplifier preamp stage or power amp stage how do you know if the tube amplifier is High Plate amplifier stage or a Low Plate amplifier stage? I'm guessing High Plate and Low Plate mean the Gain Ratio of the stage?
That's a really nice score. Man, I'd almost kill to have someone sit with me and help repair my Sencore Z-meter. For some reason I just can't figure out why the capacitance setting doesn't work. Every other function on that thing works properly but that...even the leakage function. I tried all the low hanging fruit and replaced every single electrolytic cap in the unit in hopes that would nuke the problem from orbit...still nothing. Sigh. The guys on the Antique Radio forum were extremely helpful with a lot of information but unfortunately I haven't been able to lick the problem yet.
Hi Great video. I live in England and have an RCP 314 tube tester from 1944. Can you please help me. I need a tube set up table for this set and cannot find one this side of the pond. Can you suggest a supplier or Internet site where I can purchase one from. Failing that can you look at the schematic for the set and advise how to set the "shunt voltage" for a particular tube. I can set up the tube for any tube
Dale - I don't know the answer, so I consulted with a friend that only works on tube gear (youtube channel RadioWild), and here's what he had to say: The 8980 is what's called a "Cermet Planar Triode" made by EIMAC. This succeeds the 2C37 tube I think made by Amperex. This is a transmitting tube specifically for CW use. I have 4 other testers and none will test that tube. Not very many transmitting tubes can be tested. This I think is one of them. For more characteristics, check out - www.relltubes.com/filebase/en/src/Technical_Notes/EimacCareFeeding2.pdf
Cool! I have the Mighty Mite 4. It uses a tube. So how do I test the tube in the tube tester? I could wait until every tube I test shows up as bad. But I think it's unlikely the tube in the tester will go bad any time soon. It is used so rarely.
Thank you for next great video! I seen those tester on eBay but they are slightly expensive how simple they are. Q: Isn't better to build the same (schematic is public) like buy one? May be there is also possible improvement in circuit like using relay instead of some switches an MCU and display to inform user about tube type and so. And using this MCU to contain all those information's which is in this paper "manual"?
You certainly could build one with more modern technology (microcontroller driven setup, etc.), but there wouldn't be much of a market to sell it - so it would have to be a project driven by your own passion.
Nice video, clear and precise. I've been keeping an eye out for a tube tester for several months but everyone wants way too much money for such an old piece of gear. Eventually I'll find one from someone sane ;)
Well, I DID buy this checker. Are there better ones, sure there are. But, I didn't have any, so this one is a good unit, and certainly better than nothing. Emission testing is useful, as is the shorts test. Mutual Conductance is another useful test, but this tester doesn't do that. There is NO tester that can tell you for sure if a tube will work in your application or device, because they don't mimic the operating conditions in the device it's used it. Therefore, the testers are only good to tell you if the tube is obviously bad. They can't tell you if they're obviously good.
Vacuum tubes can exhibit many giga-/tera-ohms of resistance when off, then if we find a resistance of less then 300 Kohm on the same path when the tube is off, then it is practically shorted. This can though greatly vary depending on the application. As a rough example, it is a bit like having a mosfet that excessively leaks current from source to drain.
Also remember that typical vacuum tube circuits operate at hundreds of volts, with very high circuit impedances - so a value of 300kohms from grid to xxx (when it is supposed to look like an open circuit) can be very detrimental to circuit operation. The 300Kohms value is somewhat arbitrary, but certainly orders of magnitude less than the giga-tera ohms that the Grid should have.
There are several wearout mechanisms that can take place. The heaters can become less efficient, providing less heat over time. The primary wearout mechanism is a reduction of cathode emission. Cathode emission is via the oxide coating. There is a limit to the maximum number of electrons emitted over time. Several other factors, such as impurities and gas in the tube, can also adversely affect emissions over time.
A lot of manual labor in building one of those. I was expecting you to spray some contact cleaner on the switches. I wonder how many of those drug store testers are buried in landfills (all?).
Randy, you have to be very careful about cleaners in a tester like this. The *very* sensitive grid leakage test can be negatively impacted by the lubricant / residue left by most cleaners, since it’s designed to measure 200Mohms or more.
Do you know what a EBM 3D printer is? I know someone that built one and needs the high voltage wired up by a smart person in that field, they know the concept, built 90% of it and came to a stop when it came to the high voltage, are you interested? It's like a CRT, and the beam was able to be made with a flyback transformer and a phosphorus detector, imagine having 3D printed metal parts, if you show interest I can show video of the apparatus, there's also a RepRap called "metalica rap" that is another one, thanks, oh yea it works like a vacuum tube that's why I asked
Restoration and enjoying antique and vintage electronics is a vibrant hobby - plenty of folks (including myself) really enjoy this aspect of electronics, as well as modern equipment and technology. I'm certainly not lacking for material for my channel, that's for sure!
Fair enough. I didn't watch your video. Not interested in old tech. There is Mr. Carlson's lab for that which I also don't enjoy watching. By hey, whatever puts a smile on your face. I smile at other stuff.
No worries - I cover a lot of different areas on my channel - vintage to modern, basic to advanced, DC to RF, design to repair, etc. Let me know what you're interested in and I can add those topics to my long list of future video topics.
Anything with modern electronics will do it for me. I like your channel and watch most of your videos. Meanwhile, I'll learn to be a bit more tolerant towards what others like.
Thanks for this informative video about the Sencore TC162 Tube Tester.
I worked at Sencore for some six years, starting as a factory service technician.
The TC162 was my favorite machine to work on, having tested TV and radio electron tubes at my Dad's store since I was ten years old.
The Sencore approach was focused on the service technician determining quick "Good-?-Bad" testing, especially in home service calls, rather than complicated engineering parameters of Hickok and other testers, which I also used.
Alan, very nostalgic. As a kid in the 60's I remember the corner "candy" store, complete with soda fountain, had a tube testing console. Looking back, I find it remarkable that there were people "handy" enough to take the back off a tv or radio and pull some tubes for testing. Today, the legal liability alone would prohibit that. I enjoyed your Tek commercial before the vid as well, that is some piece of gear. Thanks, Dave
I remember the drug-store tube testers also. FYI - I have NO control over the commercials/ads that play before and during my videos. That's all determined by RUclips and Google, not me. So, I don't know what commercial you saw...
Great history/tutorial, thanks Alan. I'm privileged to own this unit's big brother, a Sencore Mu140, which partly addresses the gap between "test" and "real world" conditions. Besides shorts, leakage and emission, the Mu140 also measures transconductance; and unlike old-school Hickocks etc., does so with a 5 kHz audio test signal. It also uses an "auto grid bias" that simulates typical in-circuit biasing. Very hard for a weak tube to sneak by. Only annoyance is that (like the 162) the meter isn't graduated in uA/mA, just the stupid go/nogo bands.
I own all models of these Sencore Mighty Mights, including the TC162. Build quality of these units was state-of-the-art in their day. If you were a Radio &TV Repairman in 60s & 70s, you carried one in your truck for service calls. Good times.
HI Alan, great video on the subtleties of tube testing and its limitations. Brought back memories of my dad teaching me how to use one properly. One minor comment, the plate cap wire you mentioned can also be a grid cap as well for some tubes.
The TC 162 has the best grid leakage of any tube tester I have ever encountered; even my B&K 747 fails in this category. Yes! you are right about no tube tester can simulate the actual working condition. If I am not sure about the results, I will check it on a second tester to reduce false readings or substitute a replacement.
Thanks Alan for another great video. I have owned this same model for many years and love it. Always have had great service with Sencore products.
Next to radios this is my next weakness. Can never pass on buying another tube tester. Have all the big boy high end testers from AVO, Hickock, Tripplet, Westmore, B&K, Sencore and even have a custom laboratory tester that came out of a Westinghouse lab. My favorite is probably the Tripplet 3444 laboratory mutual conductance tester. One of the best portable testers ever made. For the average user the Sencore is a great little tester. It's one of the first testers I ever bought and tested thousands of tubes on It. Definitely one of the great emission testers.
That's a nice tester! I have one just like that. Out of curiosity, I looked into the "life test" function. When you slide the switch over, there is a one ohm resistor that goes on series to the filaments. Since emissions are usually not a problem with rectifier tubes, this will help determine the heater is wearing out. Your presentation is spot on as always!
Thanks again Bob!
I know it’s been a while, but I’m interested in this life switch function. I was thinking of incorporating it into another vintage tester I have (University TST).
I have read that it’s best to reduce the filament voltage by about 10% for a life test. Will this 1 ohm resister do that across all the filaments in this circuit?
I have one of these and a Hickok. You can build your own calibration plug using a old tube base. This tester works about as well as an emission tester can be expected to.
I'm a little late to this party having only just found this video in my feed today, but I found it useful nonetheless. I'm in the process of refurbishing a B&K 607 Tube Tester, a direct competitor to the Sencore TC162. About the only difference between the two is that the BK607 does not have the TC162's Life Test switch. I was a bit disappointed that you declined to test the 6146 tube you showed. My Kenwood TS830s uses two of those tubes. I'm trying to learn as much as I can about the radio before I tackle a full restoration and alignment on it.
The 606 will not test 12ax7 Russian made tubes
Hi Alan, Interesting video! Sencore made excellent test gear overt the years. I'm a long time user of the TV7 for testing older radio/TV/Audio tubes,. Only problem is, it doesn't test the later Compactrons. There's where the Sencore comes in handy. It's a nice portable service tester for quick emission checks. I repair pro audio gear, but also specialize in vintage vacuum tube electronics repair/restoration...tube radios, TV's, Hi-fi & guitar amplifiers, recording & broadcast studio equipment. 80% of my work is tubes, and the rest solid state. Your videos are well enjoyed by me and many of my colleagues. One of these days, I have to get my old Tek 475 scope working properly again (an old favorite). May need some advice on that project :) Keep the great videos coming.
Very good tutorial. Thanks for the grid leakage tip...to let the tube warm up!
Yes Alan Very good video and sure remember using tube test in the TV and Radio Shop, and yes good point is to wait few minutes to double check the tube if any changes happen .had a Hickok then .. &3's Alan
You are one of the best instructors I've seen.. Seriously.. Excellent.. I would love to see some videos where you walk us through some schematics and fully explain them and talk about the design decisions that go into such circuits.. Or have you thought about an electronics course, starting from basics and getting into design? Just some suggestions...
I have *several* videos where I walk through the design, schematics, etc. - both on some circuits I've designed as well as some production products. Here's a short list:
Flexible Ramp Generator: ruclips.net/video/bVahBmsvirE/видео.html
Sawtooth Waveform Generator: ruclips.net/video/ibnz5UjQ4u0/видео.html
Cascode Amplifier: ruclips.net/video/Op_I3Ke7px0/видео.html
555 Monostable: ruclips.net/video/MbWc70ZzTlI/видео.html
Basics of Gilbert Cell: ruclips.net/video/7nmmb0pqTU0/видео.html
Basics of Differential Amplifiers: ruclips.net/video/mejPNuPAHBY/видео.html
Diode Ring Mixers: ruclips.net/video/junuEwmQVQ8/видео.html
Directional Coupler: ruclips.net/video/byF1FLdbUiA/видео.html
Op Amp Basics: ruclips.net/video/K03Rom3Cs28/видео.html
Op Amp Peak Detector: ruclips.net/video/Fn5kHhNRsz0/видео.html
Op Amp Summing Amplifier: ruclips.net/video/juQtVIx1a8g/видео.html
Common Emitter Amp gain and frequency response: ruclips.net/video/NizrzRKQqII/видео.html
Common Emitter, Base and Collector amplifiers: ruclips.net/video/zXh5gMc6kyU/видео.html
Vbe Multiplier: ruclips.net/video/Obh_PIC2qqo/видео.html
AutoRanging Analog Voltmeter: ruclips.net/video/7OLGswQ7ICI/видео.html
RC Servo fun: ruclips.net/video/iaGZOO33Z-o/видео.html
Single Cell LED light: ruclips.net/video/qfgX93o8HzY/видео.html
Unique Stair-step Generator: ruclips.net/video/Kqb5zcrgv7s/видео.html
Simple Transistor Curve tracer using stair-step: ruclips.net/video/ZOLLoa2fH24/видео.html
5 Transistor ESR meter: ruclips.net/video/3fiUZZlveS0/видео.html
Heathkit CW Transceiver walk-though: ruclips.net/video/rPM1vvGorTo/видео.html
MFJ CW Transciever walk-though: ruclips.net/video/2QSwXv2RJzw/видео.html
TenTec 1254 Shortwave Receiver walk-through: ruclips.net/video/dZNN5RnOdt8/видео.html
S-meter upgrade to 1254 receiver: ruclips.net/video/5yhMOcpHS7Q/видео.html
Wadley Loop receiver: ruclips.net/video/JvS9tBWAc1s/видео.html
w2aew Thank you. I really appreciate the reply and links.. Have a great Thanksgiving!!
Continued ......from tube data manuals but cannot calculate the shunt voltage. Many thanks and keep creating brilliant videos. Best wishes Bill
Cool device! Reminds me of when I was a kid repairing old WW2 tube radios and none of the equipment had polarized plugs or grounding. One time I had accidentally plugged in the tester backwards which made the case hot. I can't remember what I was holding, but in one hand I had a soldering iron or telephone and with the other I touched the controls and that thing shocked the the living hell out of me (arm-to-arm across my chest too! thank goodness for being young, ha).
Very Informative. Thank you for taking the time to share this.
Still have an older Sencore, plus a WWII military Mutual Transconductance tester for which I made a bank of modern sockets with a set of a dozen slide switches (1P10T) to do the switching. You had to do some "hoop-jumping" to translate from the Tube Characteristics manual to settings on the tester, but it was all I could afford as a one-man electronics repair shop back in the early '70s. I quit TV repair when TVs went to using $100 swap-out modules instead of discrete component repairs. No way for a one-man shop to stock every board for every TV.
Nice video, whenever I see one of a tube tester video I get the urge to go and buy one, then I remember I only have one bit of gear that has tubes, a HealthKit it12.
I know what you mean. I only have two or three items with tubes, but being a bit of a test equipment junkie, I had to have at least one tester.
Great presentation of equipment, that seems to never get old. The wiring inside of the tester is amazing. Don't those wires get brittle over time? Great show, thanks!
Surprisingly the wires are still in good shape - only about 45 years old ;-)
Reminds me of some Saturday mornings from my childhood at Radio Shack or the local Drugstore (Dart Drug I think was a predecessor to Target? 🤔 We had a 25" Magnivox that ate tubes like crazy
I've had and used one of these for years. It is a great Go NoGo tester while nit a Mutual Conductance tester it is a good piece of test equipment! WB4IVG Laurin
I remember my Dad working on TV sets for Sears, he would stick a tube on the tester and then thump the tube with his fingers to see whether the tube was noisy or not. A lot of times they were after warming up. To think these were in grocery stores and people who didn’t know anything about electronics were diagnosing their own sets. Tube sales were high:-)
You beat me to the punch! Tap that tube and watch the short light to see if it flashes.
Yes, that's a good point, that I meant to make in the video. It is a good idea to lightly thump the tube especially during the shorts test.
Not just intermittent shorts; sometimes tubes would become "microphonic". Vibration would change the µ so that any chassis vibration could set up noise or even audio feedback. A tap while in circuit would cause a thump or damped ringing in the speaker.
One of the tube manufacturers made a give-away item which was a pencil with a t-shaped assembly for the eraser. It made the pencil into a tube-tapping hammer with eraser faces. I haven't seen the one I had for half a century. I probably used it as a pencil until it got too short and tossed it. (Who could foresee collectables and eBay back in the day?)
[A couple minutes later] LOL - Evidently somebody did. I see dozens of eraser-hammer pencils on eBay. Oddly I didn't see any from a tube manufacturer. Search eBay for [ pencil double eraser ] The perfect weight, the resilience of the cedar shaft, and the elasticity of the eraser made a pretty good tube tapper as I recall. I bet the erasers are hard as rocks by now.
The downside of using a pencil around any high voltages was that concealed within the cedar shaft was a pretty good conductor - a stick of graphite. I now recall that this was why I tossed my tube-thumper. One ZAP did it for me.
my first job when separated from the service in 1968 was Secore Electronics, that is if this is the company that started in Addison, Illinois
thank you, used such (similar) device 60 years ago in a Radio-Shop , when I was young, had no money and had to test old tubes, which I found in broken radios. Hihihihi.
The Emissions Test is an in series current meter Ammeter measuring the current from cathode to plate? The LIFE Test is putting a Load/parallel resistance on the plate of the tube to ground?
Fire bottles, got to love 'em!
I have a Hickok 533A. This is the model that uses a light bulb as a fuse to protect itself. I found gum wrapper wrapped around the base of the bulb to short out the bulb and bypass it. Not safe at all.
What are Novars, Nuvistors, Compactrons tubes used for and why aren't they used more often in electronic circuit designs? I think most tube testers will measure and test Novars, Nuvistors and Compactrons
Thank for another great video Alan. Very good point you mentioned about waiting on the leakage test. That is a trap for young players. I have one solid state tester, EMC model 215. Never use it much. After many years (mid 80's) I got my old HICKOK 800A back that I sold after closing the TV shop down. Thanks for sharing.
Hah! I had an EMC 213. Wish I still had it. I built it from a kit, wired up all those sockets... I rather liked that unit. Got two other testers now, one newer one and an older unit that has the sockets for the pre-WWII stuff.
When measure a vacuum tube amplifier preamp stage or power amp stage how do you know if the tube amplifier is High Plate amplifier stage or a Low Plate amplifier stage? I'm guessing High Plate and Low Plate mean the Gain Ratio of the stage?
Excellent review! One question: Is there an adapter so that you can test 4 pin tubes? Thanks again.
I'm not sure.
That's a really nice score. Man, I'd almost kill to have someone sit with me and help repair my Sencore Z-meter. For some reason I just can't figure out why the capacitance setting doesn't work. Every other function on that thing works properly but that...even the leakage function. I tried all the low hanging fruit and replaced every single electrolytic cap in the unit in hopes that would nuke the problem from orbit...still nothing. Sigh. The guys on the Antique Radio forum were extremely helpful with a lot of information but unfortunately I haven't been able to lick the problem yet.
Hi Great video. I live in England and have an RCP 314 tube tester from 1944. Can you please help me. I need a tube set up table for this set and cannot find one this side of the pond. Can you suggest a supplier or Internet site where I can purchase one from. Failing that can you look at the schematic for the set and advise how to set the "shunt voltage" for a particular tube. I can set up the tube for any tube
How does the pin elimination switch work? I couldn’t see the linkage in the video. Thanks!
Thanks I want to buy like this tube tester where I found it
Could you help me with a question? I need a tester for 8980 tubes. Mayber, the first type you mentioned. The trans-inductance type.
Dale - I don't know the answer, so I consulted with a friend that only works on tube gear (youtube channel RadioWild), and here's what he had to say:
The 8980 is what's called a "Cermet Planar Triode" made by EIMAC. This succeeds the 2C37 tube I think made by Amperex. This is a transmitting tube specifically for CW use. I have 4 other testers and none will test that tube. Not very many transmitting tubes can be tested. This I think is one of them. For more characteristics, check out - www.relltubes.com/filebase/en/src/Technical_Notes/EimacCareFeeding2.pdf
w2aew ,,, I was wrong on the tube number. It's a 8908.
Could you do a video on IIP3 points? Love the channel! Thanks for the videos.
That is a topic that is on my list...
w2aew Oh sorry didn't know that. I'll check it out thanks.
Cool! I have the Mighty Mite 4. It uses a tube. So how do I test the tube in the tube tester? I could wait until every tube I test shows up as bad. But I think it's unlikely the tube in the tester will go bad any time soon. It is used so rarely.
Maybe the best way is to get a known good spare tube, and then periodically swap and test...
Thank you for next great video! I seen those tester on eBay but they are slightly expensive how simple they are. Q: Isn't better to build the same (schematic is public) like buy one? May be there is also possible improvement in circuit like using relay instead of some switches an MCU and display to inform user about tube type and so. And using this MCU to contain all those information's which is in this paper "manual"?
You certainly could build one with more modern technology (microcontroller driven setup, etc.), but there wouldn't be much of a market to sell it - so it would have to be a project driven by your own passion.
Nice video, clear and precise. I've been keeping an eye out for a tube tester for several months but everyone wants way too much money for such an old piece of gear. Eventually I'll find one from someone sane ;)
Take a look at your local estate sales and auctions, you'll find one!
@@creyflan That has struck me as a good place to look for some things...
its good to see der dee lcr meter in ur bench too.. how do you like it?
Only had it a few weeks, but I like it so far.
OK... would YOU buy this checker? Is there any better model? Is emission testing the most important test?
Well, I DID buy this checker. Are there better ones, sure there are. But, I didn't have any, so this one is a good unit, and certainly better than nothing. Emission testing is useful, as is the shorts test. Mutual Conductance is another useful test, but this tester doesn't do that. There is NO tester that can tell you for sure if a tube will work in your application or device, because they don't mimic the operating conditions in the device it's used it. Therefore, the testers are only good to tell you if the tube is obviously bad. They can't tell you if they're obviously good.
Could you explain how 300K is considered a short? I thought shorts were a single-digit or fractional number of ohms. Thx.
Vacuum tubes can exhibit many giga-/tera-ohms of resistance when off, then if we find a resistance of less then 300 Kohm on the same path when the tube is off, then it is practically shorted. This can though greatly vary depending on the application.
As a rough example, it is a bit like having a mosfet that excessively leaks current from source to drain.
I guess I found the particular 300K value curious, but your explanation makes good sense. Appreciated!
Also remember that typical vacuum tube circuits operate at hundreds of volts, with very high circuit impedances - so a value of 300kohms from grid to xxx (when it is supposed to look like an open circuit) can be very detrimental to circuit operation. The 300Kohms value is somewhat arbitrary, but certainly orders of magnitude less than the giga-tera ohms that the Grid should have.
Is this tester able to test the old four prong tubes?
No, it does not.
Thanks Alan.
What causes a tube to gradually go bad? I mean, I get a "blown" tube, but not the incremental failure.
There are several wearout mechanisms that can take place. The heaters can become less efficient, providing less heat over time. The primary wearout mechanism is a reduction of cathode emission. Cathode emission is via the oxide coating. There is a limit to the maximum number of electrons emitted over time. Several other factors, such as impurities and gas in the tube, can also adversely affect emissions over time.
thanks. It's all sort of magic to me.
Great tutorial thank you !!
And for those that like this tube stuff I recommend shango066 channel.
Please fix the power cord!
Nice choice of tubes to test... *cough* Kenwood Hybrid *cough*
Yep. ;-)
A lot of manual labor in building one of those. I was expecting you to spray some contact cleaner on the switches. I wonder how many of those drug store testers are buried in landfills (all?).
Randy, you have to be very careful about cleaners in a tester like this. The *very* sensitive grid leakage test can be negatively impacted by the lubricant / residue left by most cleaners, since it’s designed to measure 200Mohms or more.
Do you know what a EBM 3D printer is? I know someone that built one and needs the high voltage wired up by a smart person in that field, they know the concept, built 90% of it and came to a stop when it came to the high voltage, are you interested? It's like a CRT, and the beam was able to be made with a flyback transformer and a phosphorus detector, imagine having 3D printed metal parts, if you show interest I can show video of the apparatus, there's also a RepRap called "metalica rap" that is another one, thanks, oh yea it works like a vacuum tube that's why I asked
I am somewhat familiar with the technology, but never been close to one or worked on one. It's a bit outside of my field unfortunately.
Here's the video footage ruclips.net/video/rUjEBT4d7uM/видео.html
Let the dead rest in peace. No need to drag out tech from 50 years ago, if you lack material for your channel.
Vacuum tube fanatics love this kind of stuff though. Don't ask me why, they just do.
Restoration and enjoying antique and vintage electronics is a vibrant hobby - plenty of folks (including myself) really enjoy this aspect of electronics, as well as modern equipment and technology. I'm certainly not lacking for material for my channel, that's for sure!
Fair enough. I didn't watch your video. Not interested in old tech. There is Mr. Carlson's lab for that which I also don't enjoy watching.
By hey, whatever puts a smile on your face. I smile at other stuff.
No worries - I cover a lot of different areas on my channel - vintage to modern, basic to advanced, DC to RF, design to repair, etc. Let me know what you're interested in and I can add those topics to my long list of future video topics.
Anything with modern electronics will do it for me. I like your channel and watch most of your videos.
Meanwhile, I'll learn to be a bit more tolerant towards what others like.