[Milsurplus] GO-9 Project: Why the Resistor?

[David Stinson]

Dear Smart People:
Please take a look at the GO-9 transmitter schematic attached. The 837 
MO and 837 IA tubes are supplied filament voltage from the same buss.  
However, the connection to the 837 IA tube goes through R-312, a 4.5 Ohm 
20 Watt resistor (red arrow).  At the 0.7 Amp current of the 837, this 
is going to drop around 3 Volts, reducing the tubes filament voltage 
from 12.6 VAC 800Hz down to 9.6 V.  I haven't found a mention of this in 
the manual's circuit description.  Why would they do this?

TNX OM ES 73 DE Dave AB5S



-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20191022/11e7d566/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: bjpbgmfejakfjgon.jpg
Type: image/jpeg
Size: 85546 bytes
Desc: not available
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20191022/11e7d566/attachment-0001.jpg>