Nice L/R Indicator.? ?40? untested.  
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Odd additional marking, maybe an early ILS setup? or such. Ben 
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sorting out my spare tubes. if anyone needs 55 tubes let me know.
send messages direct.
Ben
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Re: converting 1154 to linesr IQ modulstion
This is a big ongoing project thst is half complete. It involves the following:
1. The top tank tuning capacitor is converted to split stator by using threaded nylon rod to hold the vanes and putting an insulating spacer between the two halves. This allows me to run the two PT15s in push-pull.
2. All tank coils are replaced with new ones for the desired bands 160.80 and 40 and are split in the center and routed through the tank bandswitch to the primary of a big toroid to which the 1250v HT is applied on a center tap. The secondary of the toroid has the lower of the tank tuning capacitors across it and its many taps go to one of the antenna? tap switches. This effectively makes a balanced Pi circuit.
3. A big toroid is used to drive both PT15s in push pull? between gris and filament, but neither is ground. Instead a tap somewhete grid and filament ends is grounded so operatin is half way between ground grid and grounded cathode. This is multifilar winding to pass heater citrent to both filaments and insert grid bias. The primary of the transformer is a center tapped 2 +2 turns to accept the output of the balanced Pi citcuit of the driver, which is two B5? base 807 copy attempts and replace the VT105? triodes.?
4. The modulstor is an I and a Q beam deflection tube, the sum of whose outputs drives the driver grids. The deflection plates take I and Q modulsting signals, which SSB? come from a ployphase RC quafrature network.? The hrids of the beam deflection tubes are driven by quafrature RF using a wideband LC quadrature network covering 1.75 to 10MHz.
5. Power supply is a 12v transistor Hbridge rnning at 209KHz drivibg a toroid to provide 259v. Venter tap of the primary gives a vobstantv6v for filsments. The 259v secondary dtives a push-pull Cockroft Walton 5 stage rectifier giving 259, 500 and 1250v. Psu is pretty small and fits in a screened box in the back whete the big green resistors were.
I will post pictures when complete.
Paul
Only trouble is, its no longer a T1154. Why mod it? it would be easier to build a ham rig from scratch. Hey ho.
Ben
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converting 1154 to linesr IQ modulstion
This is a big ongoing project thst is half complete. It involves the following:
1. The top tank tuning capacitor is converted to split stator by using threaded nylon rod to hold the vanes and putting an insulating spacer between the two halves. This allows me to run the two PT15s in push-pull.
2. All tank coils are replaced with new ones for the desired bands 160.80 and 40 and are split in the center and routed through the tank bandswitch to the primary of a big toroid to which the 1250v HT is applied on a center tap. The secondary of the toroid has the lower of the tank tuning capacitors across it and its many taps go to one of the antenna? tap switches. This effectively makes a balanced Pi circuit.
3. A big toroid is used to drive both PT15s in push pull? between gris and filament, but neither is ground. Instead a tap somewhete grid and filament ends is grounded so operatin is half way between ground grid and grounded cathode. This is multifilar winding to pass heater citrent to both filaments and insert grid bias. The primary of the transformer is a center tapped 2 +2 turns to accept the output of the balanced Pi citcuit of the driver, which is two B5? base 807 copy attempts and replace the VT105? triodes.?
4. The modulstor is an I and a Q beam deflection tube, the sum of whose outputs drives the driver grids. The deflection plates take I and Q modulsting signals, which SSB? come from a ployphase RC quafrature network.? The hrids of the beam deflection tubes are driven by quafrature RF using a wideband LC quadrature network covering 1.75 to 10MHz.
5. Power supply is a 12v transistor Hbridge rnning at 209KHz drivibg a toroid to provide 259v. Venter tap of the primary gives a vobstantv6v for filsments. The 259v secondary dtives a push-pull Cockroft Walton 5 stage rectifier giving 259, 500 and 1250v. Psu is pretty small and fits in a screened box in the back whete the big green resistors were.
I will post pictures when complete.
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I was the sunday morning net operator in an ATC squadron in the '50s using 1154/1155. I have just always loved these radios,, but they have quirks Here are 2 simple things you can do to an R1155 to improve it:
1. Frequency stability: Replace the ceramic compression trimmers with Johanssons
2. SSB performance is spoiled by AGC pulling the LO. Just take AGC? off the mixer tube grid and contrive -3v fixed grid-cathode bias. I did that wirh a 3.3v zener.
If you want to do a bit more, I found some very cheap 560KHz ceramic resonators which I used within the existing IF cans to sharpen up the selectivity. I simulated proposed bandpass filter structures in FORTRAN? first to get nice flat top to the response of each can.
Paul ex-G3VEL now KX4GP
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Derrick |D Thanks for the reply Ben. Yes, plenty of info on the web, but as my 1155N came to me in pieces, there are a few issues identifying parts, wire routes etc.( I didn't have the luxury of making notes as it was taken apart!). I'm wanting to restore it to full working order including the DF section. I had another (working) 1155 many years ago which I sold. I've regretted it ever since, but hopefully will get the new one working. Luckily it hasn't been canibalised too badly, although many DF parts had been removed. (The HFCs for example, although I've fabricated new ones).? Other issues are for instance someone taking a hacksaw to the tuning slug of L40, removing the ferrite leaving only the adjusting screw! My interests are primarily older, valve receivers, and military aviation in general. Although my career was in high reliability electronics manufacturing, todays miniaturisation doesn't 'do it' for me let alone not being abled to see half the components.? Derrick
I know what you mean about seeing stuff. I recently started in microwaves, little did I realise just how small SMD parts are!!
OK about wiring etc. I can't recall seeing such detail anywhere, if needed here I have 5 or 6 sets so easy to look at another one, hi.?
There are very good component placement diagrams so one could speculate wire paths from them?
I'll see what I can find
cheers, Ben
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Derrick |D
Thanks for the reply Ben. Yes, plenty of info on the web, but as my 1155N came to me in pieces, there are a few issues identifying parts, wire routes etc.( I didn't have the luxury of making notes as it was taken apart!). I'm wanting to restore it to full working order including the DF section.
I had another (working) 1155 many years ago which I sold. I've regretted it ever since, but hopefully will get the new one working. Luckily it hasn't been canibalised too badly, although many DF parts had been removed. (The HFCs for example, although I've fabricated new ones).? Other issues are for instance someone taking a hacksaw to the tuning slug of L40, removing the ferrite leaving only the adjusting screw!
My interests are primarily older, valve receivers, and military aviation in general. Although my career was in high reliability electronics manufacturing, todays miniaturisation doesn't 'do it' for me let alone not being abled to see half the components.?
Derrick
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Lancaster T1154 trailing wire reel? ?120 Type D key? ?80  
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Many sites on the web with full info on the R1155 sets.
google is a handy tool.
-----Original Message-----
From: djdarlow via groups.io <djdarlow@...>
To: [email protected]
Sent: Wed, 2 Nov 2022 20:20
Subject: [T1154-R1155] Hello !
Hi,
have just joined the group as I'm in the process of rebuilding a R1155N receiver, and looking for relevant data and documents.
Derrick
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Hi,
have just joined the group as I'm in the process of rebuilding a R1155N receiver, and looking for relevant data and documents.
Derrick
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Hi,
have just joined the group as I'm in the process of rebuilding a R1155N receiver, and looking for relevant data and documents.
Derrick
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The rearranging has allowed me to open up the Italian Spy set, Nova, for display at last. The West Wing has a new member of staff now.
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trailing wire antenna bracket
OK, long shot but has anyone the aerial fixing unit fitted to the bottom of the trailing wire bracket? or one they can photo in hi-res so I can try and make one?  
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Ok, no R numbers on this cct so still unsure which R is u/s.?
Anyway, good luck with it.?
Ben
-----Original Message-----
From: brian.redfern@...
To: [email protected]
Sent: Sat, 9 Jan 2021 17:40
Subject: Re: [T1154-R1155] R1155 restoration
Thanks Ben, just checked my wiring on power supply and is correct for biasing resistor from 30V- to earth 5k 25w adjustable as in diagram.The resistor that burned out was R3 not R4 Sorry
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Thanks Ben, just checked my wiring on power supply and is correct for biasing resistor from 30V- to earth 5k 25w adjustable as in diagram.The resistor that burned out was R3 not R4 Sorry
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The HT neg does not go to ground but is above gnd so giving the heg bias. See pic.?
The audio amp is not needed, I simply use an o/p transformer wired backwards and an l.s. to it, more than enough audio for room listening.? ?Pin 5 straight to af o/p tranny, other side to ground.
Ben
-----Original Message-----
From: radtone999 <radtone@...>
To: [email protected]
Sent: Sat, 9 Jan 2021 15:54
Subject: [T1154-R1155] R1155 restoration
Hi All, I have just about come to the end of my R1155 restoration; haven't used it since the late 8o's I don't know what happened to the original power supply I made for it at the time, probably pinched bits for another project. Anyway, I have made another with negative bias built in as shown on various diagrams,something I didn't concern myself with back then. But there was a massive resistor that was not stock wired in which got very hot, so perhaps that was the bias; wish I had noted where exactly it was wired Ht- to LT- perhaps? Anyway, doing a HT power test through a variac on reaching 100 volts? R4 tuned into toasted smoke. I will have to recheck the wiring on this board, but wondering if this? is a biasing issue?
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Hi All, I have just about come to the end of my R1155 restoration; haven't used it since the late 8o's I don't know what happened to the original power supply I made for it at the time, probably pinched bits for another project. Anyway, I have made another with negative bias built in as shown on various diagrams,something I didn't concern myself with back then. But there was a massive resistor that was not stock wired in which got very hot, so perhaps that was the bias; wish I had noted where exactly it was wired Ht- to LT- perhaps? Anyway, doing a HT power test through a variac on reaching 100 volts? R4 tuned into toasted smoke. I will have to recheck the wiring on this board, but wondering if this? is a biasing issue?
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