[Drake] minor B-Line problem

[Garey Barrell]

Tom -

The problem is most likely the neon bulb behind the dial.  Neon bulbs 
tend to increase their "triggering" voltage with age, especially when 
they are in a "dark" area.

There are a couple of "almost official" fixes.

1.  Remove R150, the 100k resistor across the switching transistor Q10.  
This is the Drake fix, and is what they did when one came in for 
service.  R150 is located on the small board just behind the front panel 
under the chassis beneath the PTO

2.  Replace the neon bulb with an NE-2E.  The modern designator for this 
bulb is A9A.  Unfortunately, there doesn't appear to be a standard 
length for this type of bulb.  Some are too long to fit in the small 
aluminum light shade behind the dial.  This can make it difficult to 
order a replacement by mail!  Replacing the bulb can be frustrating, the 
leads are short, and the front panel must be removed to get to the 
wiring.  Three or more hands are a definite advantage!

73, Garey - K4OAH
Atlanta

Drake 2-B, 4-B & C-Line Service Supplement CDs
<www.k4oah.com>

 >
Tom McDaris wrote:
> I hope you folks can give me a tip on a B-Line problem.  Set is in fine working order except for the little light on the R-4B that is supposed to come on when you tranceive in the Receiver VFO controlled mode.  The light comes on when you first turn the R-4B on but goes out when you turn the switch to transmitter VFO control (as it should).  Problem is that when you turn the switch back to receiver control the light stays out.  I am talking about the switch on the T4XB.  Do you think the problem is in the switch or elsewhere?  Rig works fine and is clean as a whistle.  Thanks   AB8BW
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