[Milsurplus] Info wanted...

[Robert W. Downs]

Ken,

Someone probably already told you this, but the digest seems to be arrivi=
ng
slow today.  I think that you must mean the DY-88/GRC-9A.  The DM-35 is t=
he
12 volt dynamotor for the BC-604 and BC-684 VHF FM transmitters.  As you
can see from the nomenclature, the DY-88 was originally built for the
AN/GRC-9A.

TM 11-5820-474-14 (on the AN/GRC-109), in the primary power options figur=
e
on Page 9, does not show either the DY-88 or the DY-105 (24 volt in only)=

as an option.  I know that you have run your GRC-109 off of a GN-58 hand
crank generator, but didn't mention in any of our other correspondence
whether you were running it through Power Supply PP-2684/GRC-109, through=

Voltage Regulator CN-690/GRC-109 or direct to the transmitter and running=

the receiver some other way.  Since the PP-2684 itself will run off of 6
VDC and 75-260 VAC, I assume the latter two, unless you want to run the
AN/GRC-9 mobile.  Else why would you want to use the DY-88?  The CN-690
drops the 500 and 6.3 VDC from the generator to 105 and 1.5 VDC for the
receiver.  Since the DY-88 ouputs these voltages directly, my guess is th=
at
you could run the GRC-109 off of the dynamotor only through the CN-690 or=

off of the vibrator supply for the receiver and the dynamotor for the
transmitter, without the CN-690.  Since the T-784 lacks the switching to
start the dynamotor part of the DY-88, you'll have to outboard that
function.  But the vibrator part starts when you put a load on the 1.4 VD=
C
filament supply, so the vibrator supply should start by hooking the R-100=
4
up to the DY-88 and turning the DY-88 on (or to Standby-Receive).  I'd
check the filament voltage immediately after turning it on for the first
time.  Although the tube counts in the R-1004 and in the GRC-9 (and
BC-1306) receivers are the same, the tube types are not.

>>
3) Does anyone know what the procedure is for making the DM-35 =

dynamotor/vibrator power supply work with the AN/GRC-109?  =

<

73
Robert Downs
<RWDowns_WA5CAB@compuserve.com>
Houston