[CQ-Contest] Voice Keyer

[Tom Rauch]

First I have a question. How does a voice keyer send CW?? Or 
does it have a CW key output?

To correct some misinformation about the MFJ432, it has been 
ground isolated since I was given the job of reworking it a few years 
ago. The small chokes were NEVER for ground isolation, they were 
for RF isolation.

The original MFJ VK switching scheme was FET's (duh) and it 
originally had no audio isolation transformer (double duh). Nether 
were good ideas.

It was also hand wired, it is now surface mount.

As far as I am aware, the only recent problems come from a batch 
that may still be out at dealers where an assembly line inspector 
let units out that were not stuffed with all the parts, or were not 
soldered at the correct temperature in the wave solder machine. 
Since MFJ does not serial number units there is no way to trace 
these other than popping the cover and looking next to the jumper 
terminals for missing or partially soldered ferrite beads.

Other than that batch, any VK within the last two years or so 
should all work with any radio and not have any significant audio 
quality issues. If they don't, I would like to know about it because 
that means I missed something!!

73, Tom W8JI
W8JI at contesting.com 


--
CQ-Contest on WWW: http://lists.contesting.com/_cq-contest/
Administrative requests: cq-contest-REQUEST at contesting.com