The AM Forum

These two transformers are from a swap. The guy said they came out of an Alpha. No model number given. I checked them out with 120 vac in. I got these voltages out

RED 1674 VAC
OR VIO OR 42 Vct
Blu 14 vac
Yel 7.0
Any idea what they are out of. I am trying to figure what I can pull out of them.
John N8QPC

Here is my list of Alpha transformer AC voltages (AC unless DC is stated)
My guess would be model 86 or 89, Can you recheck the HVAC winding? -the manuals show more but who knows..
Both use two 3CX800s with 13.5V filaments.
The manuals are on http://bama.edebris.com/manuals/alpha/ so you may look at the schematics and see what matches. Sometimes there are options or weights stated and pics of the transformer. A clue is that there is one 15 pin connector. These are a little weird because they have but one primary winding and most Alphas have two, and some a third interconnected buck/boost. Could it be a 240V winding? There are other models and the best I can do is guess.

77DX 77SX
2x 120, 1800/2800VAC, 5VAC, ?wt-rd, wt-gry. 8877 tube 5VAC

374
2x 120 /w tap, HVDC 2200/1400 (pri.tap), 25-40VDC, 2 or 3x 8874s fil 6.3VAC

374A
2x120, 5 or 25VAC unclear connected to one 120V winding, 1100/1750VAC, 40VCT, 2x8874 fil 6.3VAC

PA-76, 76P, 76C
2x120, 25VAC (buck?) connected to one 120V winding, 1100/1750VAC, 40VCT, 2 or 3x 8874 fil 6.3VAC, option R for hi/lo HV

76A, 76PA, 76CA
2x120, 25VAC (buck?) connected to one 120V winding, 1100/1750VAC, 40VCT, 2 or 3x 8874 fil 6.3VAC, option for hi/lo HV

78
2x120, (110-130VAC/220-250VAC) 25VAC (buck?) connected to one 120V winding, 1100/1750VAC, 40VCT, 2 or 3x 8874 fil 6.3VAC, option for hi/lo HV

86
2x 110V, 25V, 1250/1885VAC, 50VCT, 7VCT, 13.5V(FIL), 2x 3CX800

89
200/220/240VAC, 1350/1900VAC, 7V, 51VCT, 13.6V(FIL), 2x 3CX800A7

91B
100/120V/200/220/240V,  2050V, 14V, 105V, 310V, 28VCT, 2x 4CX800/GU74B (12.6V fil)

PA-77
120/240V, 5V, 44VCT, HV 2400/3700VDC, one 8877 (6.3V fil)

Patrick
I tried 220 on the primary they didn't like that. I figure by wight maybe .6 kva not a lot of iron and the primary leads are pretty wimpy. I looked at all the different Alpha schematic and my old Peter Dahl catalog. The voltages look right for a 8874 box. The primary is what threw me. I wonder if they made any medical oscillators. It could be the guy I bought them from didn't know where they came from, and was blowing smoke.

John N8QPC

ETO did mri and plasma generators.

--Shane
KD6VXI

As Shane points out, ETO did  indeed make linear amplifiers for MRI.  I worked on a couple in GE MRI systems, running 3CX400A7s as I recall.   What struck me as odd was that they used 120 volt power input.   I run my ham station amps on 240, thinking that 120 vac is only for kids, lids and space cadets.   So probably stuffing 220 in would be "inappropriate".

The 120 V winding is for short talkers.


KLC

http://hamgallery.com/Tribute/W2OY/w2oy2.wav

There may be a few onboard who don't know about W2OY, a 75m fixture from the 60s.  The otherwise obscure references in the above posts are to his distinctive style.