I watched both video, and now I feel confident opening my SWR Workingman 2004 and check what cause that constant hum and background noise. Thank you so much for sharing this tutorial with us. Cheers from Canada.
Terry,thanks again for your nice video's on amp repaires.The way you're explaining all the matters to the repairs,the tips you give,how to work best,in what position and on which pace. Also your tip on the special lamp with big lens,is a very good one. Back to SWR amps.I have a Silverado open at the bench now.The complain on this amp,is first,when you switch it off power,it gives a big "boom" on the speakers(a complainment on more SWR amps,like Redheads),so in this combo it already has blown all its 4 8"speakers,which were replaced already by previous owner.So my idea is/was to install a switch to disconnect the speakers from the amp,before putting the powerswitch of the amp off. I hope this will work to prevent the boom" happening again.
Wonderfull video Sir. I'm a certified tech and i'm still learning. i did learn a couple of new things from your video. Thank's a lot and keeo it up. Best regards.
Terry, another great repair video! You have probably answered this before, but do you sell the power tester used iat the end of the video, or provide schematic, parts list, etc? If for sale, price? Thanks! Tom
Awesome!!! I have an SWR Bass 350 amp. Is there any way to prevent the popping sound that is heard when turning the amp on and off? Here is SWR's explanation: "Upon powering up, don't be surprised if you hear a small pop. This is absolutely normal and will not cause damage to your speaker system. (Eliminating this "power on transient" would require a component called a relay. SWR chose not to incorporate this type of component due to the fact that relays degrade signal quality and often fail, causing the unit to have no output and requiring a trip to a local service center."
Thank you so much, Terry. Amp works better than new :).I really enjoyed watching you troubleshoot and fix the amp. How is my friend, David Eden doing? :)
those front 2 PSU caps are missing the tops because they are right by the 5 watt resistors for the +/-15V front end zener regulated power supply. the heat from those resistors is enough to cause the heatshrink on the caps to...well...shrink...and it shrinks down around the sides of the cap towards the heat. then top caps come loose and fall out. The solder Joints for those resistors in ANY SWR bass amp should always be checked. I have seen them melt the solder right off the board they can get so hot.
Great video very informative,i have question,my solid state 100watt guitar amp seems to be running less than have its normal volume,what could make this happen ? regards for any help. Andrew
Hi Terry. I've been watching a few of your videos now (very impressed BTW), but what's puzzling me is where are you attaching the scope, and how/what probes are you using. I recently acquired a Farnell DTV20 20MHz scope and have some probes. I just need to know where to hook them up safely whilst monitoring an amp wihtout blowing up my scope. Perhaps you could do a video of how to carry out this monitoring in detail.
+Terry Dayton Thanks Terry I'll look forward to it. I found a bit more information in your Champ video, but it would be nice to have a dedicated 'How to' procedure for this. My scope was a steal at £30 but I don't want to hook it up to the wrong thing in the wrong way and let the blue smoke out. BTW I think you should try a nice Tempranillo Rioja. Goes well on it's own or with anything really. I've got my home built JTM 45 clone sat waiting for a mains transformer at the minute (the first one was bad). It's my first amp build and I'm really looking forward to its completion.
+Andy Wragg Hello again Andy. I just wrapped up the oscilloscope amp checkout video. Will have it posted tonight. Take a look at my new posting. Will be on very soon. Let me know if this is what your looking for. TD
I watched both video, and now I feel confident opening my SWR Workingman 2004 and check what cause that constant hum and background noise. Thank you so much for sharing this tutorial with us. Cheers from Canada.
Terry,thanks again for your nice video's on amp repaires.The way you're explaining all the matters to the repairs,the tips you give,how to work best,in what position and on which pace.
Also your tip on the special lamp with big lens,is a very good one.
Back to SWR amps.I have a Silverado open at the bench now.The complain on this amp,is first,when you switch it off power,it gives a big "boom" on the speakers(a complainment on more SWR amps,like Redheads),so in this combo it already has blown all its 4 8"speakers,which were replaced already by previous owner.So my idea is/was to install a switch to disconnect the speakers from the amp,before putting the powerswitch of the amp off.
I hope this will work to prevent the boom" happening again.
Wonderfull video Sir. I'm a certified tech and i'm still learning. i did learn a couple of new things from your video. Thank's a lot and keeo it up. Best regards.
Terry, another great repair video! You have probably answered this before, but do you sell the power tester used iat the end of the video, or provide schematic, parts list, etc? If for sale, price? Thanks! Tom
Awesome!!! I have an SWR Bass 350 amp. Is there any way to prevent the popping sound that is heard when turning the amp on and off? Here is SWR's explanation:
"Upon powering up, don't be surprised if you hear a small pop. This is absolutely normal
and will not cause damage to your speaker system.
(Eliminating this "power on transient" would require a component called a relay. SWR chose not to incorporate this type of component due to the fact that relays degrade signal quality and often fail, causing the unit to have no output and requiring a trip to a local service center."
Keith Copeland same problem but I have a buzz and the limiter and clip lights come on a few seconds after powering off
Thank you so much, Terry. Amp works better than new :).I really enjoyed watching you troubleshoot and fix the amp. How is my friend, David Eden doing? :)
to limit the inrush current (for a first test) put a 100W light bulb in series to your variac output
those front 2 PSU caps are missing the tops because they are right by the 5 watt resistors for the +/-15V front end zener regulated power supply. the heat from those resistors is enough to cause the heatshrink on the caps to...well...shrink...and it shrinks down around the sides of the cap towards the heat. then top caps come loose and fall out. The solder Joints for those resistors in ANY SWR bass amp should always be checked. I have seen them melt the solder right off the board they can get so hot.
Another excellent video!
Great video very informative,i have question,my solid state 100watt guitar amp seems to be running less than have its normal volume,what could make this happen ?
regards for any help.
Andrew
+MrAndfio Is the sound distorted? If so you may have a bad driver transistor
Hi Terry. I've been watching a few of your videos now (very impressed BTW), but what's puzzling me is where are you attaching the scope, and how/what probes are you using. I recently acquired a Farnell DTV20 20MHz scope and have some probes. I just need to know where to hook them up safely whilst monitoring an amp wihtout blowing up my scope. Perhaps you could do a video of how to carry out this monitoring in detail.
+Andy Wragg Hello Andy, I will post a video this weekend detailing oscilloscope amp output monitoring. Thanks for the info
+Terry Dayton Thanks Terry I'll look forward to it. I found a bit more information in your Champ video, but it would be nice to have a dedicated 'How to' procedure for this. My scope was a steal at £30 but I don't want to hook it up to the wrong thing in the wrong way and let the blue smoke out. BTW I think you should try a nice Tempranillo Rioja. Goes well on it's own or with anything really. I've got my home built JTM 45 clone sat waiting for a mains transformer at the minute (the first one was bad). It's my first amp build and I'm really looking forward to its completion.
+Andy Wragg Hello again Andy. I just wrapped up the oscilloscope amp checkout video. Will have it posted tonight. Take a look at my new posting. Will be on very soon. Let me know if this is what your looking for. TD
+Terry Dayton Hi Terry, Yeah I saw that and have made the appropriate comments. Many thanks again.
@@d-labelectronics Did you remove the rust on the cabinet?
The smoke test should trip a fuse right?
Smoke test! Why doesn't that trip a fuse?
Did you remove the rust D-lab?
good job sir
i m fixing same kind but its bass750,
I am learning how to pull some cool words here...lol.. '' cool as an cucumber '' :D
SORRY FOR SPELLING MISTAKE,ON LETTER BELLOW,SHOULD BE( HALF ITS NORMAL VOLUME,
How do i locate the driver transistor?
regards
+MrAndfio Your amp wont have a driver transformer. There is a solid state driver section on the PCB.
Dont know whats wrong with my spelling lately,should have been (below) not bellow
Hi T man, I'd like to see the inner workings of your dummy load tester. Looks lie a good home brew project, to steal your ideas from, hi hi. Don
***** Well, that is a trade secret! haha. I may have a schematic. Made these as a D-lab product years back.
You’re not going to clean the old paste
Sound is distorted,