I assembled my orginal Eros phono about 10-12 years ago. At the time, I'm sure all the resistance and voltage test checked out, because I did use it for several years before getting away from playing LPs.
A couple of months ago, for some reason I decided to blow the dust off my LP's get back to spinning vinyl. At some point while listening to an album, I left the volume up on my amp while flipping sides and noticed a strange hum.
After checking all of the components in the signal chain, I determined that the hum was originating from the Eros. It was not strong enough to be heard while playing an album, but it was there.
I had a few othter things to take care of on my stereo, and today, I finally got around to troubleshooting the Eros.
As per the manual, I started with a resistance check. Off the bat, I noticed that terminals 2, 4, 9, 10, 12, and 14 where all reading 19% to 20% high. Terminals 6 and 7 tested fine.
I says, OK and turn the amp around to test the other terminal strip.
Immiediantly, I noticed a bit of a lead sitting across T21 and T22. That didn't look right, so I went back through the dox and could not see that was ever supposed to be there. So, I clipped it, and the hum went away.
Yahoo! Probable ground loop, and I ceased my troubleshooting at this point.
Away, with all that out of the way, my question (and purpose of this post) is do I need to be concerned with those higher than spec resistance values on the front terminal strip? I know from my tinkering around with tube based guitar amps, 20% variances from the spec'd values are no big deal. Just didn't know if that would apply to the Eros (or other Bottlehead components)
Thanks
Don
« Last Edit: May 27, 2024, 01:32:36 AM by dhherring »
Vinyl: Technics SL-1200GR2 w/Denon DL-110 -> Eros Phono Pre -> Stereomour -> Klipsch Heresys
Digital: Jriver MC/Tidal -> Schiit Bifrost 2/64 -> Mainline -> Sennheiser HD-650
