Power Supply for Elmac AF-67

[ka1tdq]

I got a clean Elmac AF-67 off eBay some time ago and had to make a power supply for it.  I finally got around to finishing it and here it is.  I'm using two 12 volt transformers back-to-back to work as an isolation transformer, and then double the 120 volts for the low voltage.  B+ is 300 volts with a filter choke.  That same toroidal transformer has a couple 6.3 volt windings. 

I'm going light on the voltage, but I'm just trying to have it make a little RF.  It's more of a show piece rig than an actual daily operational rig.

Jon

[N3GTE]

So @ 300vdc how much rf does it make? My little HW will make abt 10W at the 300v level (switch in low). In high (450v) on AM puts out abt 30W and few more on CW. Very similar tx w/6L6's x 807. Have had the bug to put it back on the but not much motivation. Maybe we'll catch you on 40 sometime.

Terry N3GTE

[ka1tdq]

I've always liked the look of those Bandmasters, but I've never owned one.  The Elmac is similar with 6L6's modulating a 6146 instead.

I haven't turned the transmitter on yet.  I still has the original electrolytics and bias battery.  I need to replace the caps and get rid of the battery.  I'm sure it'll put out about 10+ watts.  It's a perfect level to drive a little 3-500 amp. 

I have a crystal for 3870 but I'm sure nobody would hear me.  40 meters is a possibility and I could probably use the onboard VFO (gasp). 

Look for me somewhere between 6 and 8 MHz.

Jon

[KB2WIG]

Nice package.



klc

[ka1tdq]

I found a crystal for 7293 that I had forgotten about in my stash.  I was about as excited as Steve Martin was in the movie 'The Jerk' when he saw his name in the phone book. 

I just need to go into the transmitter and make the improvements.  The rest is all done. 

Jon