Posts: 1,824
Threads: 114
Joined: Jul 2014
City: Sneedville, TN
As you may have read, I have problems with my speaker for the 37-640 project I am working on. Just in case nobody has a K34 speaker they will sell me, and I have to repair what I have, I have ordered this output transformer from AES.
https://www.tubesandmore.com/products/tr...output-8-w They have a 10% off sale, so I figured I'd grab it while I could, such things are always useful eventually, even if I can't use it now. I read the reviews, and they said they work OK in such push-pull circuits. I am wondering if some of you might look at it, and give me your opinions on how it might work out as a replacement for the one in my 37-640. Any advice will be appreciated.
Posts: 93
Threads: 20
Joined: Aug 2014
City: Greenville, TX
Just disconnect one lead going to the voice coil and measure the resistance. It will either be closer to 4 or 8 Ohms. Use that info to determine which terminals to use on the transformer.
Posts: 16,317
Threads: 569
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
It is closer to 1 ohm in K34.
In early philcos it was from 0.3 ohm , 0.7 was popular. This one is 1.1, I think.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 1,824
Threads: 114
Joined: Jul 2014
City: Sneedville, TN
Yes, Mike, it is in the library here, 1.11 ohms.
Posts: 16,317
Threads: 569
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
Magic number.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
