This is just to confirm successful swap of this relay with parts mentioned in other threads.
For the 7250PE, this is relay RY801, listed with the NAD part number in the thread title.
Once removed, this is an NEC sealed relay with NEC part number MR72A-24, 6L4. 6 pins, DPST. I can find no specs for this discontinued series of relays on the internet.
Omron G2R-2A-DC24 is an exact fit replacement. 5 amp contacts, non-sealed.
Both relays have 1100 ohm coil resistance, so no need to change resistor in series with the coil (R806, 820 ohm). I measured voltage drop across the coil as 25VDC before and after the swap.
There is a sealed version of this relay available from Omron. Slightly more expensive with 4 amp contacts. I was unsure of the contact rating for the NEC relay, so went with the 5 amp non-sealed option.
I had one channel with some occasional low volume crackle. Fine at higher volume. Described many times here as "punch through" phenomenon, so I had suspected worn relay contacts. Once replaced, I cut the old NEC relay open for some failure analysis, and there was only minor pitting of the contacts. Noise came back in a few days and I ended up doing a more rigorous cleaning of the speaker selector switch with deoxit, which had been crackling when jiggled. Apparently I was not thorough enough with my cleaning efforts the first time through. Only cost me a few bucks for the new relay, and it is possible there actually were two weak links in the connection.
For the 7250PE, this is relay RY801, listed with the NAD part number in the thread title.
Once removed, this is an NEC sealed relay with NEC part number MR72A-24, 6L4. 6 pins, DPST. I can find no specs for this discontinued series of relays on the internet.
Omron G2R-2A-DC24 is an exact fit replacement. 5 amp contacts, non-sealed.
Both relays have 1100 ohm coil resistance, so no need to change resistor in series with the coil (R806, 820 ohm). I measured voltage drop across the coil as 25VDC before and after the swap.
There is a sealed version of this relay available from Omron. Slightly more expensive with 4 amp contacts. I was unsure of the contact rating for the NEC relay, so went with the 5 amp non-sealed option.
I had one channel with some occasional low volume crackle. Fine at higher volume. Described many times here as "punch through" phenomenon, so I had suspected worn relay contacts. Once replaced, I cut the old NEC relay open for some failure analysis, and there was only minor pitting of the contacts. Noise came back in a few days and I ended up doing a more rigorous cleaning of the speaker selector switch with deoxit, which had been crackling when jiggled. Apparently I was not thorough enough with my cleaning efforts the first time through. Only cost me a few bucks for the new relay, and it is possible there actually were two weak links in the connection.