R1155 Master Switch

[James01]

Hi, Im new to this site. I've come here to see if anyone can help me with my R1155!.
I bought it as spares/repairs. It has had the DF section removed, along with a few switches connected to that!. Including the Master switch!.
I'm not sure if this is a big problem, I only want to use it as a radio, or at least get it working again. I'm pretty sure the master switch should have been set to A.V.C., Could I wire it up so its permanently on AVC ?.
I have powered it, using a known good power supply,and connected earphones.
all the valves glow, but no audio. the visual indicator glows green, but doesn't change when moving the tuning knob.(aerial connected).
I've also swapped the VR100 valves around, still nothing.
I was told if you touch the aerial wire to the valve caps,you will get a crackle in the phones, which you do!.
Any thoughts would be greatly appreciated!.
James

[Herald1360]

As you've probably seen from initial inspection, the R1155 was not exactly designed for ease of service access! Given their intended use in bombers, most sets would have had a short life anyway.

If you try the search facility in this forum, there is some useful info on the set to be found and at least one member has done a comprehensive rebuild.

Setting the master switch to AVC is fine for general AM listening, but if you want to resolve CW or SSB signals, the AVC should be off, though it's not a great set for SSB anyway- that mode only came into common use later.

The R1155 was always a bit of a poor relation amongst the "surplus" sets with somewhat limited frequency coverage and all the DF bits were generally seen as useless bits which could better be replaced by output stage and power supply circuits etc which is why few survive in unmolested condition. This was reflected in the prices charged at the time. Nowadays its association with Lancasters etc makes it more collectable than some of its much better performing contemporaries.

[AC/HL]

Hi James,
Removing the DF bits was a popular mod. when these receivers were commonly available, making space for a PSU and output stage.
The manual states that OMNI is the normal position for communications, giving manual control of RF, FC and IF gains.
The AVC position naturally replaces the manual gain with automatic.
Whoever removed the master switch must have chosen one of the two options, unless you also have an AVC on/off switch.
The manual is available on the VMARS site, but if you use the search box at the top of the page you will find quite a lot of info on this classic receiver.

[James01]

What Im finding difficult is how to wire it for just audio, the circuit isnt the easiest to follow!

[AC/HL]

Was it sold as working, or is it a mass of disconnected wires?
It may just have developed a fault.

[AC/HL]

You may already have this, but it should help to find the problem.

[Sean Williams]

James, let me know if you are really struggling - I am only down the road, and have repaired a number of the 1155s

Cheers
Sean

[James01]

Ive got it working!, A couple of the capacitors were disconnected for some reason. Thanks for the offer anyway Sean.
I bought it as spares/repairs Bill,so Im rather pleased its working now.
The magic eye is a bit tempramental, it probably needs replacing.
Thanks for your help everyone!.
James

[Herald1360]

If the magic eye actually glows green, it's doing better than a lot of them!

Intermittency is more likely to be caused by something other than the eye itself.

Oh, congratulations on getting something out of it! The real fun now starts if you want to get it working as well as it did 60 odd years ago

[M0FYA Andy]

James,
I would recommend Peter Holtham's book on restoring the R1155 -

http://www.r1155.blogspot.co.uk/

I have no connection other than as a satisfied purchaser of his book!

Andy