In article ,
(Chris Suslowicz) in
rec.radio.amateur.boatanchors writ:


"ron_ayling" wrote:

Hi, I've recently purchased what looks like an old Ex WD unit, with no
identity plates, and I'd really like to identify it, I'm sure its a
receiver though it could be a converter of some description, quite
large front panel 280 by 170mm 300mm deep, centre left of the front
panel are three controls marked Aerial RF and Oscillator, each having a
little window that clicks round 0 to 9, to the right is a paxolin
panel with test points marked V1 to V10, bottom of panel sockets left
to right marked RF input, Output, Power Input, Gain control, inside the
three front panel controls connect to what looks like a front end box
which held two valves marked VR138 and VR137, there are then six IF
cans with a single coil inside and six valve holders alongside marked
VR65...

With those valves, it's ex-RAF, probably late WW2 to 1950s vintage.

VR137 is an EC52 low power VHF transmitting triode on B9G base.
VR138 is unlisted in anything I have to hand, unfortunately.
VR65 is an SP61 pentode (100MHz max frequency) on Maxda Octal base.

The EC52 is capable of 7 watts and 300MHz, so it's a transceiver
or transponder of some sort, I'd guess. (Possibly IFF?)


Dunno, can't remember ever seeing one of those as a power amp.
Usually they were the local oscillator for VHF kit. I don't recognise
the stuff as described, but the Gee nav receiver had a similar valve
line-up if my memory is right. The main chassis was the R1355, with
6? SP61 IF amps, and the RF26/7 plugins were EF54 RF, EF54 Mixer, EC52
LO. Suggest a repackaged Gee rx to the OP. Tuned 20-70 Mc/s, IF
7Mc/s, again trusting my memory.

R1355 wasn't much use for anything, save that the RF26/7 units were
stripped down for the very well made 2 gang and single gang 75pf
tuning caps, and the Muirhead epicyclic drive. Many amateurs bought
one of the RF2?-25 plugins for a lifetime's supply of 30 pf beehive
trimmers, I'll be leaving half a dozen beehives to my heirs.

j.