[Johnson] Viking Ranger VFO Problems/Access

[Mark Donaldson]

 Hi Bill,
You have just discovered the most common problem with Rangers, Valiants etc., the so call Chernobyl resistor. I won't get into what is going on just Google it. To answer your question, you only need to remove the left side (as you are facing the front of the transmitter it will be on your left side) side panel on the VFO, don't forget the nuts on the bottom side. I have done several of these repairs and it can be done without further disassembly of the VFO. If you remove the front panel you will risk breaking the disk on the reduction drive.
73s,
Mark WA1QHQ
    On Monday, July 22, 2019, 10:13:19 AM EDT, Bill Stewart <cwopr at embarqmail.com> wrote:  
 
 GM All, 
My Ranger (manual dated 1954) VFO started drifting with key down no matter how long the warm-up is, so 
I took the top off the VFO compartment and found the OB2 to have a large white, internal, spot at the top of 
the tube. Also the area around the hole, in the phenolic board, where the tube goes thru, is charred and cracked. 
Obviously a lot of heat was there for a while. Also in a short check, with the power on, a lot of flashing inside 
the OB2 and it gets very hot. I suspect that R3 has changed value drastically. I was able to remove the side 
plate on the VFO and can see that R3 is cracked. Now the main question is does the front panel have to come 
off to get the VFO box off (I'm suspecting it does) . All the bottom nuts are off and only the shaft is keeping the 
box from coming off. I have taken the VFO dial off and am down to a large nut. Just wanna make sure before I 
get into what looks like a real P-I-B job. 

A bit more to the story. This Ranger has the keyer mod and the xmtr was a kit. The wiring technique is not all 
that good. The xmtr worked good for a while after I got it. But the keyer began to need adjustment. I could 
not get the adjustment needed and looking at the keyer wiring, decided to rewire it. The keyer worked. The 
drifting started after the keyer rewiring. Maybe coincidence or did I foul up something?? 

If I ever get the VFO box off, I will cut a slot in it's front so it will slide off over the VFO shaft. Don't recall 
having this issue when I went into the Navigator VFO. 

Tnx for any tips, suggestions, etc. 
73 de Bill K4JYS 
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