View Full Version : Help in wiring Altec 9442A transformer primary from 110v to 220v

10-06-2009, 05:34 AM
Hi all,
I just purchase a Altec 9442A anniversary edition and a Altec 9444a power amp. how ever , it is original intent for for U.S market. so the primary transformer is wire for 110v operation voltage. Can anyone Please highlight to me on how to wire the main transformer input to accept 220v or 240v?

Thank you.

10-06-2009, 08:38 AM

10-07-2009, 01:25 AM
Thank you for sending me the link to the manual for Altec 9442A , But due to lack of knowledge in reading schematic diagram. I still cannot figure out on how to wire the primary voltage circuit for the amp.

Link for Altec9442A:

I found the link to wire Altec model 9444A . It show in a more simply diagram
eg: TB1(1-10) TB2(1-10) to wire the primary circuit for different voltage.
Link for Altec9444A:
http://www.altecpro.com/pdfs/vintage/ElectronicsAndTransformers/powerAmps/9444A%20Power%20Amplifier%20Manual.pdf But the Altec 9442A manual does not show the same type of simply diagram as in 9444A.:(
I had ring a local shop for help in re-strapping the primary circuit to 240v but was told that will charge between 80-100 dollar for the service and owner must provide a schematic. :(:(:(
Hope you can help.
Once again, Thank you.

10-07-2009, 01:30 AM
Altec 9442A amp schematic

10-09-2009, 07:39 AM
In the schematic the primaries of the transformer are wired in parallel, they need to wired in series. If I had the amp in front of me it would take about 10 min to do. If I could see a picture of the the current wiring I might be able to help.

01-03-2010, 03:58 AM
got this 9442A from a 2nd hand shop. i opened this while reading the posts and found that it was not wired as per schematic here. i traced the wiring and thought that on this one, the primary was already wired in series.

i checked the fuse which was still okay, and hoping it won't pop, i plugged this thing into 230V. no pop, indicator lights seemed okay. my unit, as it was wired, works fine with 230V power supply.