Anyone who owns HP105B (later model) please check the voltage....

[tkamiya]

Whoever owns HP105B with HP10811 oscillator, please check the voltage at pin 14 of the OCXO and pin 15, the ground?  Do you read 24V or 18.7V?

[Bill158]

Whoever owns HP105B with HP10811 oscillator, please check the voltage at pin 14 of the OCXO and pin 15, the ground?  Do you read 24V or 18.7V?

    Mine is about 18 volts because of the A1A3 power supply assembly that the 10811/10544 oscillator module plugs into.  The A1A3 circuit has a 18 volt regulator IC (A1U1) that reduces the 24 volts from the 105B power supply.  Then there is another IC (A1A3 U1) that reduces the 18 volts to 12 volts for the oscillator supply.  See the pdf "hp-00105-6100-figs.pdf" attached.  At least this is what my 105B has installed.
Bill

[tkamiya]

Thank you.  That's what I get also.

I wanted to confirm it with other owners as HP's diagrams are so hard to read.  I took out the oscillator board, and on back of it, there is a screen printing that says 18V as well.  I didn't see that before.