Terry I'm confused most of the time. Trying to make sense of the Alpha
numbering system is pretty weird. I mostly think in terms of the ones I see
the most and that is the three tube model. Here's what the old manual says:
"The Alpha 76A, 76PA, and 76CA are self-contained high frequency
linear amplifiers capable of bla bla bla...
The 76A series is tunable over the range 1.8-2.0 mHz plus 3-22 mHz,
optimized for convenience in the amateur bands 15 through 160 meters.
Export models only (with E suffix) have six bands extending to 30 mHz,
including the 10 meter band."
You are right, in the specifications for the 76A it lists two 8874 tubes.
The 76PA is identical except the tube compliment is three 8874's.
The 76CA is the 76PA with the heavy duty Hypersil transformer which reduces
weight by 10 pounds. There's also an option 'L' which is the lightweight
Hypersil transformer and reduces weight by 20 pounds. I special ordered
this lightweight transformer from Peter Dahl for the rigs that went to Togo.
Power output is down a little with that unit but those guys are really
trying to keep the weight down.
Liscensed amateurs can open up the bandswitch to cover 10 meters. I've
never seen one that didn't already cover 10.
All the amplifiers mentioned here have a pair of meters on the front. Early
76 rigs only had one meter and the cabinet size is a little different. Not
too many of those around but if you're looking to buy one you need all the
info you can get.
Each one of the 8874's is good for about 500 watts output.
I have not decided how to handle the two-tube 76 in regards to the 3CX800
upgrade. The two 8874's are mounted nearest the front. There is no hole
for the rear tube so that presents a bit of a hurdle since the forward and
the rear sockets are utilized in the upgrade. The 374A is the same
story...two tubes mounted near the front.
At 04:19 PM 3/12/97 -0500, you wrote:
>At 11:49 AM 3/12/97 -0500, you wrote:
>>Terry that sounds like a good buy but you must be careful. You can pay $250
>>each for those 8874's on the used market. Some have found them for
>>less...some folks pay more.
>>There are three of those in the rig.
>
>Thanks for the info but I'm still a little confused. I understood that the
>76A has two tubes and the 76P has 3 tubes. I believe that the 76 that is for
>sale only has two tubes. What would be the expected output of the two tube
>version?
>
>73 de Terry KK6T
>
>
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