Hello All,
I'm working on a Zenith Console model H880 (aka. 8H20Z). When there's no record playing a hissy sound can be heard through the speaker. Is this normal or can that "FM hiss" be quieted a bit? All the paper and filter capacitors were replaced, the cartridge was replaced. What else should be done? I replaced the 12AT7 because there was a lot of microphonic sound coming from it.

Thanks,

Dave

:Hello All,
: I'm working on a Zenith Console model H880 (aka. 8H20Z). When there's no record playing a hissy sound can be heard through the speaker. Is this normal or can that "FM hiss" be quieted a bit? All the paper and filter capacitors were replaced, the cartridge was replaced. What else should be done? I replaced the 12AT7 because there was a lot of microphonic sound coming from it.
:
:Thanks,
:
:Dave
HI Dave
I would suggest checking continuity between tone arm Needle/Cartridge too chassis, in particular the Ground/Shield Wire.

Mark

Mark,
Sheilded/Ground wire? I don't see anything like that. I only see a wire with a Phono plug on the end of it and the motor power wire. Those are the only wires attached to the turntable.
I'll look over the service data again and see where another wire might go. I'll also try connecting a clip lead from the turntable directly to the chassis.

Thanks,

Dave
::Hello All,
:: I'm working on a Zenith Console model H880 (aka. 8H20Z). When there's no record playing a hissy sound can be heard through the speaker. Is this normal or can that "FM hiss" be quieted a bit? All the paper and filter capacitors were replaced, the cartridge was replaced. What else should be done? I replaced the 12AT7 because there was a lot of microphonic sound coming from it.
::
::Thanks,
::
::Dave
:HI Dave
: I would suggest checking continuity between tone arm Needle/Cartridge too chassis, in particular the Ground/Shield Wire.
:
:Mark

Check the wiring on eith end of the tone arm and check for continuity and corrosion where the shielding is connected to the ground.

Damn, I'm getting old forgot how to spell my name...

David: What mark meant was that in a lot of sets the two wires coming from the tone arm are shielded, not a seperate wire. This prevents (hopefully) your picking up RF interference which is apparently whats happening. Another point was made-make sure your connections are secure or you will pick it up there too. PL

:Mark,
: Sheilded/Ground wire? I don't see anything like that. I only see a wire with a Phono plug on the end of it and the motor power wire. Those are the only wires attached to the turntable.
: I'll look over the service data again and see where another wire might go. I'll also try connecting a clip lead from the turntable directly to the chassis.
:
:Thanks,
:
:Dave
:::Hello All,
::: I'm working on a Zenith Console model H880 (aka. 8H20Z). When there's no record playing a hissy sound can be heard through the speaker. Is this normal or can that "FM hiss" be quieted a bit? All the paper and filter capacitors were replaced, the cartridge was replaced. What else should be done? I replaced the 12AT7 because there was a lot of microphonic sound coming from it.
:::
:::Thanks,
:::
:::Dave
::HI Dave
:: I would suggest checking continuity between tone arm Needle/Cartridge too chassis, in particular the Ground/Shield Wire.
::
::Mark