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Powerdoc last won the day on August 4

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About Powerdoc

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    1/2W Resistor
  • Birthday 10/19/1947

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    Atlanta, GA

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  1. Thanks B-Man. The problem with rotating it is that the diameter is 35mm and it interferes with the capacitors near it. I have it rotated so as to interfere with the least neighboring components.
  2. Thanks again! I'm going to go through my changes today again possibly to dismount/remount the caps and the 1 resistor I changed. Bugs me that I'm going backwards here! I may reprint the manual I have, for the schematic pages, on 11x17 paper just to make following the traces easier.
  3. thanks; getting to the voltages again tomorrow; was wondering if constant recycling of the standby button to get it to turn on was a problem; still can't figure out why it transiently stopped going into protection. C954 was one that I replaced.
  4. The enemy of good is better....Last night, after re-soldering a couple of questionable solder joints voila it didn't go to protect and the speaker relays were working. Still no display. I looked at the board and some more caps looked somewhat suspect so I got some new ones today, inserted them and it's going into protect again. (emoji: hit myself in the head). I checked my work, twice, made sure the caps were oriented +/- correctly and that there was a proper capacitance tested in circuit. I'm perplexed! In any case I hope that the IC601 which drives the readout isn't bad as it isn't available apparently. Picture shows the large filter caps which had to be McGyver'd to get them to fit. Yes I know the exposed lugs are a safety hazard and that will be protected IF I CAN EVER GET THIS TO WORK! All the black caps have been replaced. The saga continues!
  5. Well, it's I again. Got the new 8200/80 caps, installed them (one is soldered into the PCB directly and the other is zip-tied upside down to it and connected to the PCB by 18ga wire. Plugged it in again and nothing new: Screen is blank and it goes into protection in about 7 seconds. Measured the voltage at the new 8200 caps and it's 71v (not much leeway from the 80v rating). All fuses are intact. Looking at the PCB with stronger glasses (now up to 4x power) I see a couple more questionable caps with some ? leakage on the board and I'm going to go to the schematic and see if they would make any power difference. Some corrosion around a couple of resistors made it impossible to measure so I may just go ahead and replace those too. I need the practice soldering. As RobertR has suggested I'm going to look at the VR's. Will make effort to see where the display gets its power and work from there. I feel certain I'll learn a lot more about electronics and electronic diagnosis before this is all over. Not that I really NEED another piece of operating audio equipment.
  6. Thanks for the replies. One of these days I'll post some of my tube porn and records, when they are put in the Kallax and Expedit shelves but we're going to redo the floors so wife says keep in the boxes in our basement area. I kept the screen in the roller but never have rolled it up! Easier to mount with the roller intact, just 2 hooks. Repurposing the cabinet was a chore. The "doors" are inset and because of that there was not a commercial hinge which would swing out far enough so the mechanism includes a hinge and a slide so to open ,the whole door assembly slides forward then can swing open. Works well since it doesn't get opened and closed so often. I've had projectors since the 3 tube Zenith which had an s-vhs adapter, and that was probably 30 to 35 years ago. My kids loved to play video games on the 100" "screen" which was the wall painted with a reflective white paint. Had Vandersteen 2's on the sides and 2 center speakers in parallel, one above and one below the viewing area. Don't remember the rear speakers but I had a 12" Klipsch sub. Was great at the time! See the pic below but mine was ceiling mounted. I was the only "kid" on the block with one. Usually you saw those in bars. Had to go into it to reverse the image as it was setup from the factory for floor mounting. S-VHS adapter never did work well though. I just put away the bar/dot generator that I used to readjust the convergence. One thing I remember about it was the price: $2500. My local Zenith dealer had to special order it for me and there was no internet to get it at a discount price. Mount secured to studs in the ceiling because this thing must have weighed 70lb. The second pic is from an ad for the house when the people who owned it after we put it on the market. The Zenith is visible on the ceiling and the cabinet on the right side held the stereo stuff and VCR's and all the associated switching equipment. Where the cabinet is at the far end of the room is where we projected the image and you can see the upper center channel speaker.
  7. Thanks; can read schematics; have the manual. The power supply cuts off after just a few seconds which I assume is the protection circuit.
  8. RobertR: Thanks for the information. I saw one of your prior posts that referred to a resistor which I checked and it was ok. Will see what happens with the new filter caps. Can the power modules be checked for shorts in circuit? Thanks! One thing about the power regulators-at least they have some sort of heat sink. I have some other equipment that was "audiophile" quality that don't and the circuit board traces to them have actually lifted off the board. I'm going to add a stick-on sink to each one of the ones on the 772
  9. Not particularly exciting anymore; my ears have the quality of cubic zirconia while my mind is still a diamond! The cabinet is a re-purposed Barzilay which had pull-out drawers on the sides which I converted to doors so I could put equipment into the cabinet. Originally there was a well for a turntable under the top which hinges at the back and the equipment was vertical inside. On the right is an Onkyo TX-NR 809 which powers the center, surround and rear surrounds. In the middle section, which does not open from the front, is a Moscode 300 which was modified by someone in Ca. according to the original owner and this powers the front speakers which are JBL L100 t3's (no they are not trapezoidal in shape, that's just my wide angle lens distorting.) The turntable is a B&O Linear this week, the center speaker a Mirage, and the RTR this week is a Revox A-77. On the left side of the cabinet is CD/DVD storage and an Oppo 93 with modded output boards. I'll sometimes use an Otari RTR but it's too tall when I watch movies and blocks the screen. If you look carefully, you'll see the shadow of the Epson projector which is 2K. My surrounds are bipolar Klipsch and the rear surrounds are a company that doesn't exist anymore and for the life of me I can't remember. They too are bipolar. Just finished wiring them a couple of weeks ago. There's also a Velodyne sub hidden in my desk which has an open side (I think the original owner of my house had his CPU there). 2nd image shows the surround and the rear surrounds as well as the projector. Fortunately, the joists in the ceiling run in the right direction so I could get to the ceiling for installation as there is open basement on one side of the room. Instruments in the back are for my grandchildren to bang on when they come down. Record storage is the usual Ikea Expedit.
  10. Just ordered 2 35mm wide ones and I'll lay them on the side tie them together and run leads to the board......hopefully. They arrive on Wednesday. Thanks
  11. You're right, the diameter is the key. What I may do is remove the old caps and see if I can just lay the cans on their side and run leads to the board. No suppliers seem to have any that are smaller than 35mm and the originals are just slightly more than 25mm. If anyone has other ideas just let me know. I'm not such a purist that I'd object to ideas other than the original orientation; I just want sound. Even looked at 10k caps, which I may use anyway just for some extra oomph.
  12. Thanks. My intention as you stated is not to power up 'til I can get the new filter caps. I didn't mean to look for another web site, I was looking for forums in this site; there doesn't seem to be one just for the receivers.
  13. But I only have 2 of them. I can't see the voltage on yours. The spec for the capacitor is 80v. thanks though!
  14. Am going to get a snap-in locally and see if it fits. The spacing looks ok but the termination looks like it's too wide for the circuit board.
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