[WRL] WANTED 755 VFO parts unit

[ars.w5jo at gmail.com]

I tried replacing the 6AU6 with the 6AH6 and could not see any difference. 
I have both the 755 and the 755A and neither varied.

My 755 has a 1K, 1 W resistor between the two sections of the PS 
electrolytic filter capacitor, whereas the 755A that I have has a choke. 
Both of mine were factory build and had one previous owner before me, he did 
not open the case on either.

Like any WRL equipment there are differences in various examples of the same 
model number.  Both are stable after warm up, but neither are as stable as 
the VFO in my Champ 300A.

Jim
W5JO

-----Original Message----- 


The plain WRL 755 does have one tube inside the shield.  However, both the 
755 that I had back in 1959 and the 755 that I have now, were/are very 
stable after about a 15-minute warm up.  I was the second owner of the first 
755 and I don't know how many had owned my present 755.  However, both were 
"factory" built.  That is, not the kit version that WRL offered.  I don't 
know if being "factory built" has any major influence on the stability.


Of course, there are all sorts of variables and different units can 
certainly act differently due to all sorts of things.  I haven't tried 
replacing the 6AU6 with a 6AH6.  Doing so would probably increase the 
stability even more like in the Heath VF-1 and Johnson 122.

Glen, K9STH