Altec 1569A Amplifiers

[bearwandaloid]

I just bought a pair of 1569A amplifiers and would like to know if the tubes need to be biased?

[Todd W. White]

ALWAYS!

37.5 volts, as I recall...

[bearwandaloid]

Thanks for the fast response. How is the Biasing done? Is there a manual for the 1569A that tells how? Any information would be greatly appreciated.

[Todd W. White]

The schematic shows the voltages. You find the pot, get your voltmeter, and turn, turn, turn (albeit CAREFULLY!).

<font color="#FFFFFF" size="1">[ August 04, 2004 10:46 AM: Message edited by: Todd W. White ]</font>

[bearwandaloid]

Once again, thanks for the reply. I looked at the schematic, and P2 should be adjusted to 37V. Where should I place the DMM leads while adjusting? Thanks for all the help.

[jimafm]

Just curious; how much does a pair of these babys cost?

[Todd W. White]

I have three from my personal stash that are for sale - one has been fully tested by IraTec ProAudio Repair and meets factory specs for a 9442A, the other two need a power supply capacitor installed, which Ira will do as part of the selling price.

If interested, drop me a line at [email protected]