On Feb 15, 3:00*pm, Engineer wrote:
Hi, all.
I am comtemplating the refurbishing of an R1155 receiver (not sure
what model) - actually, not bought yet. *Courtesy of the present
owner, it's just on the bench for evaluation. Unfortunately, it is in
rather rough shape, viz:
-- DF tubes missing (not really a problem)
-- Problem: Someone had started to install a 6K6 o/p tube in place of
the VR101/6R7 det/audio output tube and has screwed it up badly (Not
by present owner!)
-- I can't find the phones o/p transformer (designated L30) anywhere
in the chassis - not even the mounting holes!
-- I don't know where the audio detector diode circuit has gone! *I
understand that V7 (a VR101/6R7) is the AVC detector and BFO osc. tube
and that V8 (same tube type, but missing in my set), is the det/AF
tube.
-- eye tube is present but almost totally faded on test.
-- I don't have any sockets for the front-of-set plugs (I'll do some
work around.)

All tubes test good and I've several spares. *Dial is old style, i.e.
direct and 100:1, and works well.

Q1: Am I advised to replace the original det/AF tube and use an
extwernal amplifier to drive a speaker, or to complete a proper
replacement with a 6K6 and speaker OPT, adding a 1N34A point contact
RF diode as a detector (I've done the latter on a couple of vintage
commercial radio refurbishings.)

Q2: I have the schematic but would appreciate pointers to decent R1155
websites.

One last question (Q3): Is the IF 460 KHz or 560 KHz? I've seen
reference to both numbers.

My objective is to retore this set for BC and SW band listening with
an external power supply (which I have), audio amplifier (which I
have, that's if I don't pursue the 6K6 route) and a speaker (not
phones.)

Thanks for all replies and any other R1155 advice gratefully recieved.
Please also feel free to email me at "analogdino at(aboy) rogers dot
(ty as they) com" - suitably decoded!

Cheers,
Roger

Had one over 60 years ago. You are probably already aware that the
chassis is not the B- or HT- connection. In other words if you have a
power supply which has it's B negative (HT negative) connected to
chassis; very common because aluminum can capacitors are often mounted
with the negative in contact with chassis; you cannot connect the two
chassis together!! So study the set diagram carefully; IIRC there is a
resistor chain in the HT negative feed to produce a small amount of
bias voltage. I know I made quite a mess of mine around age 14 and
then had a bad power transformer which leaked 230 volts AC to the
chassis. Shame really wish had it today! Mine had the Aluminum case,
and the older style dial. The 'Odd' BL63 double triode powered the DF
meter I think. The EB34 double diode was much the same, I think as a
6H6?
Good luck