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I've been following your progress and you've done a very nice job! Jerry

OK, I put the main amp back into the circuit and made sure the pins connected correctly. The right channel (which plays), DC offset floats from zero +/- 0.010V, Idle Current does not register on the meter. The left channel (doesn't play), DC offset floats worse at zero +/-0.100 but the Idle...

This unit was re-capped before I received it. The main caps are all Nichicon KG(M) Gold Tune 6800 uF 63V. The relay voltages must have been coil readings when I look closer. J813, J814, J815 & J816 are all 1.08V, I didn't note +/-. I have been wondering about the transformer outputs but I...

Impressive! Nice work Jailtime. You guys inspire us neanderthals. Jerry

Hi guys, after replacing all the 2SA798s with pairs of KSA992s and replacing all 4 trimmers, nothing improved and I actually lost volume in both channels. While installing the KSA992 pairs I was super cautious to get the correct pin outs. I kept the old 2SA798s and trimmers which all bench test...

Thanks for the comments Steven. I looked at those as an option but not being schooled in electronics I was concerned with what setting to start with and I didn't know if it is possible to bench set them before installation. This unit is not pristine so the appearance is not a concern as long as...

New trimmers make sense to me. Is there a preferred source for these? I gave it a go on Digikey and Mouser sights and found these 201's in Digikey, they appear inverted compared to the Marantz 202's for the 1k ohm pots. I'm not having any luck finding the same mounting size 2k ohm pots with the...

It's good to be back! It's burning some brain cells since I'm not skilled in electronics but I find it to be very compelling work. I am starting research on transistor replacements and that will be added to the spread sheet and I'm thinking about adding each transistor from the part list in the...

Hi Jaltime, I did get the left channel back by cleaning the relay contacts. As far as isolating my low volume output I have not isolated the signal using those jacks. I'll test that. In my mind's eye I don't see a correlation back to the pre-amp for my lack of getting offset or bias readings...

Wow this looks very similar to my issues on my 2285B. I've already learned one thing from Catrafter's post so I'll keep tabs on your progress. Good Luck with this project! Jerry

OK, progress just stalled. I let the receiver run for a while and the left channel started to make a periodic popping noise and I don't have much power. As noted before I cannot get offset or bias voltages to register. I did measure no load voltages for each transistor on 3 boards. Each test...

Well I'm making progress. I measured all the voltages on each single and paired transistors on the Pre Amp board. The voltages were off as much as 2 volts on some but both channels had balance and none of them were flat out failed. I'll address those once I get everything functioning. While I...

That thing sure is cute and there's an awful lot of room under the hood! I lent a can of DeOxit to a co-worker who had one of those and all he did was clean the switches and he was amazed at the sound. Nice work! Jerry

Thanks Jailtime! It's good to hear from you also! Thanks for the heads up. This is a good unit for me to improve my electronics skill set, which is really minimum. I'll test voltages then I may just shotgun these and see how I do.

Thanks Tom! After my last post I continued to research those dual transistors and found that they were Monolithic Transistor Pairs. It got a lot easier once I added the 2S in front of the search. I really appreciate your information on the DC voltages. I planned on testing voltages relative to...

OK guys you're off the hook. I isolated the RCA connectors and inserted a patch cord into each one individually then tested for switched and non-switched posts. These are wired correctly when compared to the schematic. NOW, #2, an electronic component question that I'm having no luck...

Catrafter gave me the idea of fitting both of my cap pairs into the existng clamps with filler blocks. Worked out nicely. Jerry

It's been quite a while since I've posted and now I have a new project. A fellow AK'er offered me a 2285B with the left channel not working after he followed my re-cap and binder post project. Eventually I accepted the conditions and now I'm finally digging into the first of a couple of issues...

I'm impressed! There are many work arounds for these caps and I've now seen 2 versions that I like better than the one I copied from Catrafter and this is one of them for sure. Nice work! I'll keep this one in mind. I would like to know more about how you created your 'star-ground' system. Jerry

JBLman did a nice job with standard caps and clamps and an aluminum plate. Here's a link to a page on my 2285b recap where he posted his; http://www.audiokarma.org/forums/showthread.php?t=420274&page=6 I used Catrafters' approach and mine turned out fine. Jerry

I believe that I bought my EQ-10 at about the same time that I got my 2285b in 1978. There was an EQ-20 also.

Nice catch! You sure did a beautiful job on that re-cap. Hope you love it as much as I do mine! Enjoy! Jerry

Lovin' this build! You're bringing back some great memories from when I built the speakers that I'm listening to while I type this! I didn't try anything as demanding as scoops but the process sounds remarkably similar. I can't tell you how much I enjoy your play by play commentary! I'm sure...

My receiver is not easily unhooked from its location. If any one else has a 2285B on the bench Pauljuhn could use some help with the power switch. I did not do much with mine other than a cleaning. I do have one question, are you sure that it was thoroughly dry before plugging the power cord...

That's a really nice '38B! I love that blue glow!