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? on how to use a variac to power on a cr-1040

This particular amp has a lot of sentimental value to me which is why I didn't just throw the switch.

At this point, I have gathered the parts for the dim bulb tester, and just need to put it together. Even, if I don't use it, I'm sure it will come in handy in the future.

I really appreciate all the knowledgeable comments and the additional information.

Bob
 
Here is the only youtube example I could find of someone using a variac in conjunction with a dim bulb tester to power on a solid state amp.The relevant part starts at 10:00. I noticed he definitely doesn't take his time bringing the voltage up, unless he edited something.

 
Chalkboard said:
What is VFET or X-power?
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VFET (vertical field effect transistor) and rather special output transistor.Used in several power amplifiers and a C-1 pre-amplifier . X-Power supply is a switching power supply that Yamaha used in several models of Integrated amplifiers and power amplifiers.Neither of which are applicable to your CR-1040.
 
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Chalkboard said:
Here is the only youtube example I could find of someone using a variac in conjunction with a dim bulb tester to power on a solid state amp.The relevant part starts at 10:00. I noticed he definitely doesn't take his time bringing the voltage up, unless he edited something.

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I'd probably replace the big caps just because they are old.But thats just me.
 
avionic said:
I'd probably replace the big caps just because they are old.But thats just me.
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I don't know if I'm ready to replace caps, but I do want to check it over and see what kind of shape its in after 20 years of storage. And thank you for taking the time to answer my noob questions.
 
Chalkboard said:
Could you suggest a Fluke model that would have most of the functions I would need for testing and general maintenance on this amp, or any vintage audio equipment for that matter. Thank you.
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77 or 179. I use both. 117 is a little less expensive.
 
I finally got the dim bulb tester put together and am happy with the results. I did think about going with a plastic junction box, but decided I wanted the extra weight of the metal so it wouldn't turn over if I bumped the cord.

Finally having some free time, I should get this amp powered on tomorrow using both the variac and the DBT. From what I've read, it seems everything should be set to flat and the loudness off. I don't know if I need a speaker load with the volume set to zero, but will hook up some "curbside find" radio shack speakers anyway (Solo 3s.)
 

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petehall347 said:
i always check things first without speakers or dummy loads .
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I would rather not use any speakers, if I don't need too.

I did forget to mention, I plan to remove the cover and try to visually inspect the amp's condition looking for any obvious problems (and they will have to be obvious, lol) before powering it on. I will probably vacuum the interior too.
 
cr-1040.jpg cr-1040 close-up.jpg

Here is what it looks like after 20 years of storage with the cover off. I also took a close-up of the only obvious thing I could see. I don't know which board this cap is on, but it appears to be leaking and possibly another one to its right. Could storage have caused this, or was it most likely leaking before storage. I would still like to power it on, if possible. The only other problem I've noticed is the volume knob seems to be stiffer than I remember and access to the pot is blocked by a large wiring harness.
 
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Chalkboard said:
appears to be leaking
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Always some doubt when judging from pix, but that just looks like glue to me. It's worth considering a replacement of the caps, if only to try to scrape away as much of that glue as you can. The glue becomes slightly corrosive with age. But, I don't see a reason to defer your power-up testing.

Cheers,

chazix
 
chazix said:
Always some doubt when judging from pix, but that just looks like glue to me. It's worth considering a replacement of the caps, if only to try to scrape away as much of that glue as you can. The glue becomes slightly corrosive with age. But, I don't see a reason to defer your power-up testing.

Cheers,

chazix
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Thanks Chazix for your input. I went for it and all went well. For anyone trying this in the future with a 1040, the red overload light will stay on at the lower voltages. This prompted me to bring it up very quickly while watching the bulb tester (I didn't know if that overload light could be ignored at low voltages or not.) However, it does go off once the relay clicks in. I then just let it idle at voltage for about 15 minutes. Later I hooked up some radio shack speakers I plan to restore some day, if I can ever find some matching speaker grill cloth, and both channels were working just fine. It seems all the lights are working too. Now the plan is to just clean all the pots, switches, and exterior, and try and decide what to do with that cap. At least now I know it works. Eventually, I will want to service it, but I think I will practice on the cr-420 I have first, though nothing is wrong with it.

I did also get a p-550 turntable that was in storage with the 1040. I plan to bring it up in a similar fashion.
 

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