DC voltage when switching to phono

[bob orbell]

Ahha, mine is NS, and it is the one supplied with the kit from WD when Peter C was director, I will order the shorting one and fit it. Thanks Richard. Sounds like yours is the wrong one as well Colin. BOB

[Richard]

Originally Posted by bob orbell

Ahha, mine is NS, and it is the one supplied with the kit from WD when Peter C was director, I will order the shorting one and fit it. Thanks Richard. Sounds like yours is the wrong one as well Colin. BOB

Hi Bob,

Well I just checked mine in Pre3 (those in the pic are old ones from various projects in the spares box) and it too is NS so something is strange here so don't go ordering anything and I will try to find out.

[bob orbell]

Thanks Richard, do you still have Phono and PSU?, if you do, see what DC if any you get out of the output sockets. BOB

[colin.hepburn]

Hi BOB/All
Just checked mine and thers no S or NS markings on it just the pin numbered 1/12 and Pins A.B.C.D but it has in black print 2G in the middle of the four centre pins

[bob orbell]

Thinking about this, it matters not whether the switch is shorting or non-shorting, it is the relays that do the switching, and they short every input bar the one in use. BOB

[Desmodromic]

Hi Bob,

Just to be clear, are you asking for the output voltages from Phono3 or Phono3S? - I have a Phono 3 (and a Phono 2 too) and could supply the voltages from them if that would help, but I don't have a Phono 3S.

[colin.hepburn]

Originally Posted by bob orbell

Just put a meter on the output of Phono and got readings, after switch on, of between + 2volts and - 22.00volts, DC, never settles to a constant voltage, at switch off, the meter shows up to +27.00volts falling to 0. Strange.

OK for WAD phono 2
I got +22.00 volts falling to 0v

[Richard]

Originally Posted by bob orbell

Thinking about this, it matters not whether the switch is shorting or non-shorting, it is the relays that do the switching, and they short every input bar the one in use. BOB

yes of course you're right Bob. I've just checked and the inputs are already shorted when not selected.

[Richard]

Originally Posted by bob orbell

Thanks Richard, do you still have Phono and PSU?, if you do, see what DC if any you get out of the output sockets. BOB

Yes it's out of system awaiting collection so I metered the Phono3 outputs and just get a few wavering mV DC. Did you get V or mV?

[bob orbell]

It was volts Richard. never stays stable, and I have only just built it about three weeks ago, new PCB new components, the old one had been modified so many times that the tracks were lifting, it dose sound good though. Just put the meter on the outputs again, at switch on 0v, this time rising to +58v, then falling slowly to between .87v and .022. , all components are as supplied with kit apart from C7/C8 C9/C10 these are silver mica and R21/22 just a link to remove the 3.18 correction, I like it that way. BOB, puzzled