JVC RX-807V receiver. One channel distorted when SEA is enabled.

I think you misunderstood what happened. I inserted those 100k resistors myself as a modification to see if the DC voltages would stabilize. They were not part of the original circuit. After I installed them, operation returned to normal. When I changed the capacitors on that pc board to match the values in the schematic, I removed the resistors just to see if the circuit would work "as designed." (I put that in quotes because we never really know if the schematic matches what comes off the production line.) Without those resistors, the problem recurred. Therefore I reinstalled the resistors and it's all good now.

I hope that made sense.

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Hello David -- I just picked up a used RX707 that is doing the same exact thing...after he ating up the right channel is distorting badly, but only when SEA is switch ed in. From what I can take from your discussion above, you solved the pro blem by adding 100k resistors from two of the pins of IC503 to ground? Whi ch two pins get the resistors? Has that fix lasted long term? I love the fact that you can basically save a different EQ for each of your sources, s omething that today's products don't allow. Thanks for the info if you can provide it. Mike

Hi Mike,

Yes, the problem seems to have been fixed long term. The pins in question on IC503 where I installed the 100k resistors to ground were the noninverting pins, #3 and #5.

Good luck.

appears to be an actual design error m

I agree with your conclusion about the design error but how did this receiver ever work properly as initially designed? I imagine there would have been a lot of returns!

Thanks for your reply.

receiver ever work properly as initially designed"

Having dealt with leakage on PC boards it might be that internal leakage in the IC pulled it to ground but with very high resistance.

Over years and exposure to humidity it picks up other leakage from traces o n the PC board and throws off the bias.

Either that or there were high value resistors internal to the IC that have gone open over the years. the higher the value the more likely they are to open up. True of regular resistors, why not ones internal to an IC. I have actually had this on a TV once. Had to add a 1 meg to ground to fix it, or replace the IC. The 1 meg did just fine.

Hello as i observed the board i suspect the ic501 and ic 502 do you think thats the problem i baught those is from ebay

I think the ic 501 is bad

make the modification i described in the previous post. mark

Hi David. I know this thread is a bit old. How do you solder the 100k resistor to noninverting pins #3 and #5? Do you happen to have a picture of the actual solder of the resistor? Also on the resistor, what watt is the resistor? Thanks!

The wattage is unimportant. If you're using leaded resistors, use 1/8 watt and go from pins 3 and 5 to the nearest ground (like pin 4). What I would do is use a couple of smd resistors and tack them from pins 3 and 5 to pin 4 ground.

Did anyone try actually replacing those op-amps?