[Johnson] Viking 2 Modulation Transformer

Sherrill Watkins Sherrill.Watkins at dgs.virginia.gov
Thu Feb 3 09:44:56 EST 2005


Mike: One way to tell is to measure the resistance of both the primary and
secondary of the transformer and the resistance of each to the frame of the
transformer in question. Use a good quality vacuum tube high impedance type
ohmmeter. If the windings are shorted or open, the resistance measurments
will be a clue to problems with the transformer. Another method is to
directly substitute a known good transformer or measure the same resistances
of the good transformer and compare it to the transformer in question. -73-
Sherrill W. k4own. 

-----Original Message-----
From: w6we [mailto:w6we at charter.net] 
Sent: Wednesday, February 02, 2005 10:01 PM
To: johnson at mailman.qth.net
Subject: [Johnson] Viking 2 Modulation Transformer


Gents, How can I determine is the modulation transformer is still in good
condition? My problem is I cannot modulate to the suggested 250 Ma , getting
no more than 125Ma. I seem to have all the gain I need in the preamp stages.
When acquired the audio mods from ER had been installed but not the regulated
screen supply or the fixed bias on the 807's. All- in-All, it works but just
barely. need to reduce the final input to 80w or so to fully modulate with
mic gain fully open. 
Any and all input will be appreciated.( This is my first input to the forum)

Mike W6WE AMI #1526
Johnson mailing list
Home: http://mailman.qth.net/mailman/listinfo/johnson
Help: http://mailman.qth.net/mmfaq.html
Post: mailto:Johnson at mailman.qth.net


More information about the Johnson mailing list