Hi Tony, I am 63, a retired electronic technician and electronics manufacturing assembler, been working in electronics as a hobby since I was 12. However I am am still learning of better ways, or things I might have been doing improper by other technicians such as yourself. I had always been using deoxit cleaners on speaker relays using a cut down piece of business card soaked in deoxit cleaner. Just fixed a speaker relay on a Marantz 2238B two years ago. I will use the CRC QD Electronic Cleaner from now on which leaves no residue and is safe on plastics. Thank you for that tip. Subscribed, notified, and liked. You and Mr. Carlson are the best teachers of electronics on RUclips IMHO.
I worked as a tech and engineer my whole career and during that time I learned a lot from the people that worked for me. I agree we can all learn from each other. Early on we used a clear silicone thermal grease we called goose grease, later on we went to white wakefield zinc thermal compound (not conductive). That compound you are using probablky has zinc in it. I agree the fancy CPU grease has to be used with care.
Thank you so much for talking about the thermal paste! I actually replaced some of it in one of my old recivers and wondered why some transistors always blow up.
Yep. I have never done it simply because I haven't had the opportunity to this point, but sure enough, I would have reached for the CPU paste and not thought anything of it. I do believe I have Arctic Silver too...
Wow Tony, what an excellent video series! I am the original owner, and still have a Mint condition late 1970's, all metal front, Marantz 2285b reciever with the add on decoder. In the early days, when the receiver first came out, the FM Decoder made a huge difference to the listening experience coming in from the stations that offered the signal in Toronto, Canada. The best way to describe the listening experience was that the stereo signal sounded less compressed and cleaner. Would love you to do a tune up on MY Marantz Receiver! Still works great, just the volume knob develops static when not used for a while. Again thank you for sharing your knowledge 👏🏻👏🏻
I learned from home building computers, that the less heatsink compound the better. You only need just enough to cover the surface. You should be able to see through it to the surface it's applied to, as it's only supposed to fill in microscopic irregularities in the interface, between the 2 materials. I didn't know this, and used big gobs of compound on the output transistors, when I first began building Dynaco and Hafler amps, decades ago, but I got away with it. Should have been a clue, when nearly all the compound squished out, when I screwed the transistors in place.
It should be noted that, if you’re applying (electrically conductive) heat sink grease to an isolated (floating) heat sink as in the example shown, it really doesn’t matter as the screw will join the transistor tab (collector) to the heat sink anyway. If you’re worried that the floating heat sink (at the collector potential) might come in contact with nearby components, use some Kapton tape on the component leads; it can withstand high temperatures while remaining an electrical insulator. DON’T apply the Kapton tape to the heat sink; you don’t want thermally insulative tape on a heat sink!! That’s like throwing a blanket on someone burning up with fever! It should be noted that some TO-220 case transistors have a plastic/epoxy coating over the tab so you can connect these to a heat sink that’s at ground potential using a standard metal screw and any old heat sink compound. I’ve even seen a few cases where several power BJTs were paralleled on the same heat sink and the heat sink was designed to be a bus-bar for a high-current motor driver; here, electrically conductive heat sink grease would be beneficial.
Awesome video, as usual. I wouldn't recommend blowing on anything with your mouth - there is always some small amount of spit! I recommend a photography lens blower bulb, like the Giottos AA1900. Keep up the great work, don't change a thing! Thanks!
Tony some of these systems use a thing called a Smart Plate (takes the place of a metal box which contains X-RAY Film) that can have it's data offloaded to a computer for processing and printing out using a transparency printer so that doctor and surgeon can look at on their light box, if HIFI manufacturers follow YAMAHA's lead then all signal processing will happen using High-School mathematics which means that Rumble,Wow and Flutter can be deleted from the signal to leave what the studio engineer intended you to hear and some can even have DOLBY Digital 5.1 Surround or DOLBY ATMOS.
Like the desoldering vaccum gun u have there,,,when u took out the relay,,,etc. And also Like how the tuning capacitor box having the fine tuning adjustments clearly labelled too,,,I had noticed 3 sensitivity adjustments for fm frequency? I've only seen at least 2 sensitivity adjustments for fm in stereo tuner amplifiers I've repaired in the past. Am band always only have just the one,,,follow by the sensitivity adjustment transformers,,,eg yellow,white,black.
10:47 i always use a small strip of normal print paper soaked in Isopropanol, and slide this a few times through the contacts. This does the job each time.
@@len9518 , Isopropanol has also no additives, it's up to 99,99% clean alcohol. There is also a 70% version, which contains 30% destilled water for desinfection purposes.
A lot of the equipment is starting to use DSP and highly complicated algorithms to create an image that tells the doctor what problems you are suffering from, if you are interested in what is inside a lot of these machines then what about subscribing to Dexters Lab where he sometimes a teardown of medical equipment as well as the Quantel Paintbox video art system.
Ever used CRC Electro-motive to clean carbon tracks on the ceramic part of a spark plug? That does occasionally happen and requires a different plug if so.
For cleaning contacts and wafer switches I use a pencil typewriter eraser. FaberCastell EraserStik 7099B. Don't know if these are made anymore, but maybe someone has some NOS on eBay or Amazon.
Hey, if you ever have any spare time (which appears not to be the case :) ) how you go about creating your own dual package matched transistors would be nice to know as these exact transistors the A798"s are in a lot of old Roland Transistor Rhythm and Transistor Bass synthesisers. thanks Tony, always enjoy your videos, they are very informative.
It came out of a machine that was built in 1985, when they used to train us not to put our fingers across live contacts ;) Just kidding! Thanks for the comment!
Re computer processor (cpus) heat sinking. Most modern cpus have a heatsink/fan combo, with heatsink compound sandwiched in between, but they are so designed, that they will usually not be damaged, if no compound is used. These cpus will operate up to 100c, at which point they will throttle back, and keep working. I've seen a demo, of a cpu operating, not only without heatsink compound, but without it's heatsink/fan. The computer did not shut down, and the cpu throttled way back, in order to keep the temperature from exceeding 100c. This is a far cry, from the days, 20 years ago, when the cpu would "fry" within a couple of seconds, under these circumstances.
34:56 A bit of an over-generalisation I think. I use Arctic Silver 5 if I'm replacing thermal compound in a restoration/refurb (Mission Cyrus 1, Naim amp/Naim pre-amp et al and no issues at all) since it's also handy if I'm re-applying thermal compound to (say) a console CPU/GPU/APU. Arctic Silver 5 is NOT electrically conductive (although there is a warning that it may have slight capacitive properties) and it explicitly states this in its datasheet: asset.conrad.com/media10/add/160267/c1/-/en/000150352DS02/datasheet-150352-arctic-silver-arctic-silver-5-thermally-conductive-paste-89-wmk-35-g-max-temperature-130-c.pdf
Do the parts list and schematic agree with each other as well as any silkscreen print on the board? Now I have to look up the service manual. Good catch.
@RedLiver That service manual is very confusing the way it is layed out. The 2285 and 2285B are mixed together and the pages have no header to reference which amp you are looking at.
Thanks for the comment! I was worried for a minute that I may have made a mistake, so I went back and looked at t he old caps that I removed. Here is what they were: 330uF/63V 470uF/63V and 330uF/50V. I replaced both of the 330's with 63 V caps. The 470 was replaced with the same value. I agree with some of the other comments. The schematics for this old Marantz gear often contains errors. I'm sure we'll see some along the way! Thanks again!
Saving lives through heat sink compound lectures. This channel educates hands on .
Hi Tony, I am 63, a retired electronic technician and electronics manufacturing assembler, been working in electronics as a hobby since I was 12. However I am am still learning of better ways, or things I might have been doing improper by other technicians such as yourself. I had always been using deoxit cleaners on speaker relays using a cut down piece of business card soaked in deoxit cleaner. Just fixed a speaker relay on a Marantz 2238B two years ago. I will use the CRC QD Electronic Cleaner from now on which leaves no residue and is safe on plastics. Thank you for that tip. Subscribed, notified, and liked. You and Mr. Carlson are the best teachers of electronics on RUclips IMHO.
Awesome Tony, thanks for your time, videos!
I worked as a tech and engineer my whole career and during that time I learned a lot from the people that worked for me. I agree we can all learn from each other.
Early on we used a clear silicone thermal grease we called goose grease, later on we went to white wakefield zinc thermal compound (not conductive). That compound you are using probablky has zinc in it. I agree the fancy CPU grease has to be used with care.
Thank you so much for talking about the thermal paste! I actually replaced some of it in one of my old recivers and wondered why some transistors always blow up.
Yep. I have never done it simply because I haven't had the opportunity to this point, but sure enough, I would have reached for the CPU paste and not thought anything of it. I do believe I have Arctic Silver too...
Wow Tony, what an excellent video series! I am the original owner, and still have a Mint condition late 1970's, all metal front, Marantz 2285b reciever with the add on decoder. In the early days, when the receiver first came out, the FM Decoder made a huge difference to the listening experience coming in from the stations that offered the signal in Toronto, Canada. The best way to describe the listening experience was that the stereo signal sounded less compressed and cleaner. Would love you to do a tune up on MY Marantz Receiver! Still works great, just the volume knob develops static when not used for a while. Again thank you for sharing your knowledge 👏🏻👏🏻
Thanks so much Tony for sharing your knowledge,it means a lot!
Work sounds fun, especially installing a new machine bet the Installation and maintenance contracts make running your business a lot smoother.
Thanks Tony!!!This is by far my favorite RUclips channel.
I learned from home building computers, that the less heatsink compound the better. You only need just enough to cover the surface. You should be able to see through it to the surface it's applied to, as it's only supposed to fill in microscopic irregularities in the interface, between the 2 materials. I didn't know this, and used big gobs of compound on the output transistors, when I first began building Dynaco and Hafler amps, decades ago, but I got away with it. Should have been a clue, when nearly all the compound squished out, when I screwed the transistors in place.
It should be noted that, if you’re applying (electrically conductive) heat sink grease to an isolated (floating) heat sink as in the example shown, it really doesn’t matter as the screw will join the transistor tab (collector) to the heat sink anyway. If you’re worried that the floating heat sink (at the collector potential) might come in contact with nearby components, use some Kapton tape on the component leads; it can withstand high temperatures while remaining an electrical insulator. DON’T apply the Kapton tape to the heat sink; you don’t want thermally insulative tape on a heat sink!! That’s like throwing a blanket on someone burning up with fever!
It should be noted that some TO-220 case transistors have a plastic/epoxy coating over the tab so you can connect these to a heat sink that’s at ground potential using a standard metal screw and any old heat sink compound.
I’ve even seen a few cases where several power BJTs were paralleled on the same heat sink and the heat sink was designed to be a bus-bar for a high-current motor driver; here, electrically conductive heat sink grease would be beneficial.
and check with multimeter and magnifier for shorts
Thank you for sharing all those techniques Tony, greetings from the Philippines
Surprisingly there are already x-ray machine repair videos on RUclips.
Awesome video, as usual. I wouldn't recommend blowing on anything with your mouth - there is always some small amount of spit! I recommend a photography lens blower bulb, like the Giottos AA1900. Keep up the great work, don't change a thing! Thanks!
The Hako FR-300 desoldering tool, spendy, but worth every penny if you replace a lot of though hole components!
Tony some of these systems use a thing called a Smart Plate (takes the place of a metal box which contains X-RAY Film) that can have it's data offloaded to a computer for processing and printing out using a transparency printer so that doctor and surgeon can look at on their light box, if HIFI manufacturers follow YAMAHA's lead then all signal processing will happen using High-School mathematics which means that Rumble,Wow and Flutter can be deleted from the signal to leave what the studio engineer intended you to hear and some can even have DOLBY Digital 5.1 Surround or DOLBY ATMOS.
Good talk, you mention two of the 4 "C" 's Concept and Common sense. Thanks for the look.
Catching up on some older ones.. Very good stuff here !!!
Like the desoldering vaccum gun u have there,,,when u took out the relay,,,etc.
And also Like how the tuning capacitor box having the fine tuning adjustments clearly labelled too,,,I had noticed 3 sensitivity adjustments for fm frequency? I've only seen at least 2 sensitivity adjustments for fm in stereo tuner amplifiers I've repaired in the past. Am band always only have just the one,,,follow by the sensitivity adjustment transformers,,,eg yellow,white,black.
10:47 i always use a small strip of normal print paper soaked in Isopropanol, and slide this a few times through the contacts. This does the job each time.
You can use plain contact cleaner, which has no additives.
@@len9518 , Isopropanol has also no additives, it's up to 99,99% clean alcohol. There is also a 70% version, which contains 30% destilled water for desinfection purposes.
A lot of the equipment is starting to use DSP and highly complicated algorithms to create an image that tells the doctor what problems you are suffering from, if you are interested in what is inside a lot of these machines then what about subscribing to Dexters Lab where he sometimes a teardown of medical equipment as well as the Quantel Paintbox video art system.
You can really see the tops of the caps pushed out of the shrink
Ever used CRC Electro-motive to clean carbon tracks on the ceramic part of a spark plug? That does occasionally happen and requires a different plug if so.
For cleaning contacts and wafer switches I use a pencil typewriter eraser. FaberCastell EraserStik 7099B. Don't know if these are made anymore, but maybe someone has some NOS on eBay or Amazon.
Hey, if you ever have any spare time (which appears not to be the case :) ) how you go about creating your own dual package matched transistors would be nice to know as these exact transistors the A798"s are in a lot of old Roland Transistor Rhythm and Transistor Bass synthesisers. thanks Tony, always enjoy your videos, they are very informative.
That was an old Contactor they are not allowed to be used in UK or EU any more as the terminals are not finger Proof
It came out of a machine that was built in 1985, when they used to train us not to put our fingers across live contacts ;)
Just kidding! Thanks for the comment!
It is an EX- brush.
Thank goodness it wasn't a penguin on top of the telly.
Is there a more "elegant" way of re-attaching the wire-wrapped wires on the pins other than soldering them on ?
Re computer processor (cpus) heat sinking. Most modern cpus have a heatsink/fan combo, with heatsink compound sandwiched in between, but they are so designed, that they will usually not be damaged, if no compound is used. These cpus will operate up to 100c, at which point they will throttle back, and keep working. I've seen a demo, of a cpu operating, not only without heatsink compound, but without it's heatsink/fan. The computer did not shut down, and the cpu throttled way back, in order to keep the temperature from exceeding 100c. This is a far cry, from the days, 20 years ago, when the cpu would "fry" within a couple of seconds, under these circumstances.
Ceramique.
24:33 it's sleeping.
34:56 A bit of an over-generalisation I think. I use Arctic Silver 5 if I'm replacing thermal compound in a restoration/refurb (Mission Cyrus 1, Naim amp/Naim pre-amp et al and no issues at all) since it's also handy if I'm re-applying thermal compound to (say) a console CPU/GPU/APU. Arctic Silver 5 is NOT electrically conductive (although there is a warning that it may have slight capacitive properties) and it explicitly states this in its datasheet: asset.conrad.com/media10/add/160267/c1/-/en/000150352DS02/datasheet-150352-arctic-silver-arctic-silver-5-thermally-conductive-paste-89-wmk-35-g-max-temperature-130-c.pdf
I need you ! You live in the U.s ?
If so i need you ! And i pay good !
You used the wrong capacitor, 330uF instead of 470uF 🤔
@RedLiver The one that came out was a 470uF. Marantz service manuals sometimes contain errors, even the silkscreen on the pcb can be wrong.
@@M-P-X Could have been changed in the past, or a factory assembly error? What was the time point in the video please?
Do the parts list and schematic agree with each other as well as any silkscreen print on the board? Now I have to look up the service manual. Good catch.
@RedLiver That service manual is very confusing the way it is layed out. The 2285 and 2285B are mixed together and the pages have no header to reference which amp you are looking at.
Thanks for the comment! I was worried for a minute that I may have made a mistake, so I went back and looked at t he old caps that I removed. Here is what they were: 330uF/63V 470uF/63V and 330uF/50V. I replaced both of the 330's with 63 V caps. The 470 was replaced with the same value. I agree with some of the other comments. The schematics for this old Marantz gear often contains errors. I'm sure we'll see some along the way! Thanks again!