Recapped CR1020..dim bulb failure help.

I'm actually not so sure that TR609 is bad now. The one from the 2020 tested the same. I looked up a datasheet and it said it was BCE looking at the flat side from left to right. As I look at the 2020 main board a little it seems the only differences between it and the 1020 are TR611 and 612. I'm going to look into it further, but I may just be able to swap boards out.
 
if its a positive voltage at the output then its very possible the problem is in the negative side of things . burnt out resistors is what could cause this .so the voltage swings to the positive .
also could be transistors and or diodes . shorted or open in either positive or negative side of things .

hope that makes sense .
 
if its a positive voltage at the output then its very possible the problem is in the negative side of things . burnt out resistors is what could cause this .so the voltage swings to the positive .
also could be transistors and or diodes . shorted or open in either positive or negative side of things .

hope that makes sense .

Hey Pete, Good morning? I checked all of the diodes earlier and they were all good, I only have a few more transistors to go through, resistors are another story.
 
when outputs are short circuit or wrong way round the power will want to go the wrong way and try and get back to ground . higher value resistors and fuse resistors are the most likely targets and transistors and diodes .

keep on searching you will find the casualties
 
Thanks Pete that makes perfect sense to me. I actually have taken the main board out of the cr2020 parts unit I have, and went ahead and did some swapping. The 1020 is up and running sweetly now. The offset is a little higher on the left channel 13mv compared to the 0.4mv on the right, but I'm pretty sure thats within tolerable limits? Bias is holding on both channels exactly at 10mv, and she's running nice and cool especially for this series receiver. I now have the bad board out of the unit and it is a little easier to work on that way, and I will continue to try and find the culprit. This way I can listen to the new 1020 while working on it :D. I know I've said it a million times already, but thanks to both of you for your time and knowledge. Gonna finish up inside with wire ties, and making sure everything is in its place, and she'll get new LED's tonight and a freshly refinished cabinet!
 
that's good its working now .
whilst you are checking things make sure you didn't get a cap in backwards . they are just like a short if + - are reversed
 
13mv compared to the 0.4mv on the right,
Check that again...the chances of a solid 0.4mV reading are damn slim on an amp without a servo to hold it there. Are you sure you didn't read 0.4V (400mV)?
 
Check that again...the chances of a solid 0.4mV reading are damn slim on an amp without a servo to hold it there. Are you sure you didn't read 0.4V (400mV)?

Yes, I'm absolutely sure...I've checked it a dozen or so times now with two different meters, and it's been between 0 and 0.5mv each time. The other channel is reading anywhere from 12-14mv. I thought that was a good thing should I be concerned?
 
Well, Here she is all buttoned up and running sweetly. Complete recap of all boards including filter caps. About 90% Elna Silmic II and the rest are Panasonics, the big filter caps are 2 Cornell Dublier 18000uF 100v. Due to my mistake earlier in the thread, it also has new Onsemi outputs. I also changed out all of the fusistors throughout, and the resistors on the electrolytics board as the service update states, along with a new relay. Lastly, I applied new thermal paste to all transistors on heatsinks.

I cleaned all of the boards top and bottom along with the rest of the receiver...it was pretty nasty. 3 passes on all the controls and switches with deoxit, and I even polished the RCA jacks. The faceplate and knobs were cleaned with vinegar water and magic eraser...which I highly recommend trying if you haven't, as it works awesome with minimal labor. I've been using it for a while now.

I sanded the cabinet down to a 600grit and refinished it with Watco dark walnut Danish oil, and then some feed n' wax once dried. I even disassembled and refinished the bottom of the cabinet, removing the labels and screen. I sanded and repainted the top vent with a nice spray paint that matches the original pretty well (krylon brushed nickel I think) it came out very nice.

For the lights I drilled out the existing holes in the meter housing with a 5/16 bit and used 8mm white LED's. The tuner scale is a 12" LED strip with 3M adhesive tape on the underside, it fits perfectly between the scale and the faceplate (8mm wide I think). I also covered it with two layers of white fabric tape to diffuse it a bit. Its actually not as bright as it shows in some of the pics, and is evenly matched with the meter lights. The tuner pointer is a 5mm blue LED.

It sounds even better than it looks, and with the exception of my HUGE error on installing the outputs in reverse and trying to chase down shorted components(thanks again Avionic and Petehall), it wasn't too bad of a project. Hopefully it'll be around for many more years now.
 

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Looks good, the lit dial looks much better than factory.

Hey BK, Yeah I had thought of this a long while back when I first got my hands on my 2020, and right after that I saw your post of yours, so knew it would work out (credit due :D). Yes its looks way better than the pics can represent, and makes up for the one fault that this series Yamaha has...in my opinion. Thanks for the compliment!
 
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