1154/1155 pair

[G4YVM David]

Richard, you ought to write horror books...you've put the willies up me.

I really appreciate this thoughtful comment, to which I have no answer. I'll attempt to find out exactly why the valves blew...but Im losing interest now, ha ha. I really have better things to spend a grand on if Im honest.

David

[trh01uk]

David,

well, that wasn't quite my intention! Lol! However its as well to be aware of what you are getting into, especially if you haven't a lot of experience with the kit in question. You haven't said the extent of your experience with valve equipment. If its small, I wouldn't start with a T1154/R1155 - at least not without help.

There will be genuinely operational T1154/R1155 systems out there, which have been well restored. They normally only come up for sale though when the owner dies, though even then you will probably have to join the queue of other interested parties who will have already put their name on it.

As others have suggested there are simpler vintage bits of kit that can be used for a truly vintage AM radio station. In general, the older it is, the more tricky it is to get it fully working. Also the older it is, the less power output the equipment tends to have, and once you are down at anything less than 5 watts of AM carrier, you will be struggling on most UK AM nets (that depends to some extent on how good your aerial is of course).

For wartime kit, I would recommend the AR-88s for a receiver as being plentiful and reasonably straightforward to both use - and fix if it becomes necessary. They also have a built in mains supply, so no worries there. For wartime era transmitters it becomes a lot more difficult to recommend anything, that is "better" than the T1154 which you are already considering.

Most wartime transmitters with mains power units were enormous beasts, and now very rare (and expensive). Things like the Wireless Set No.53. At the moment there is only one in the UK that I know of that is regularly operational. A Wireless Set No.52 produce an excellent signal, but finding one will again be a severe challenge. And finding one with a mains supply will be another challenge. The Wireless Set No.12 produces a good account of itself, but again finding one in good order will be difficult.

A favourite for AM users is the Wireless Set No.19. That's slightly awkward in that it needs a 12V DC supply from a car battery. Trouble is that by itself it has about 2 - 4W of AM output - which is of limited use on today's amateur bands. You can boost the output with the add-on amplifier ("Amplifier RF No.2"), but again these tend to be like hens teeth, and they need another hefty dose of DC supply from (usually) a second car battery.

There are some nice American sets, which give good performance, the notable one being the ART-13 USAAF airborne transmitter. Again a bit rare, and not often heard on the air.

All in all, the T1154 is a good transmitter choice, since it produces a nice 20W of AM, which is enough to be heard over much of the UK in most conditions.

There are many more modern equipments giving excellent AM signals (e.g. C11, C12, C13 on the military front, and a number of offerings from companies like Panda, Labgear and Minimitter on the amateur/commercial front) which being slightly more recent tend to be a lot easier to get going than the wartime kit.

You shouldn't let my comments put you off an R1155/T1154 system if that's what you want. If you are inexperienced with this sort of kit though, rope in someone else who is, and who is willing to give you some help. There are lots of people on here with the necessary experience, and who will happily provide advice.

Richard

[M0FYA Andy]

A very good and thoughtful summary by Richard of various alternative vintage transmitters!

I'm not sure about the ART-13, though, definitely not for the faint-hearted with all its auto-tune gubbins!

And there's also the BC-375, the earlier US airborne transmitter used in the B17. Its four VT-4C's make the T1154's two PT15's look puny!!!

Andy

[G4YVM David]

Yes, all understood, but the T1154 was iconic in the RAF...

Im not much into voice radio, my personal love is CW and I do a lot of it in QRP, so 20w is high power stuff!

I just think the iconic status of the 1155/1154 makes it special in my eyes, plus the undeniable beauty of both sets (chiefly the colourful '54). It's a pair of radios that I have adored since I first clapped eyes on them. A salesmans dream!

I'll keep you all posted but I thank you all for your thoughts.

D

[trh01uk]

Andy,

you are quite right about the ART-13 and its auto-tuning. I was assuming that our OP would only buy something actually working, so that aspect would have been sorted. I can't recall the power unit arrangements for the set off hand, so that might be another area of concern.

I did think of the BC-375 (or BC-191), but I dismissed it because they are also quite rare, and the cost of the valves is prohibitive (since the audio-phools snap them up). Also again the power arrangements are a bit tricky. An external dynamotor system can be found, but getting leads etc often involves hefty amounts of cash to ship them over from the USA. And finally, this particular Tx has a very poor performance I am told. It chirps like mad on CW. And its distorted on AM. Its a good example of how bad things were with pre-war designs... so its not one I would recommend for a potential AM operator.

Getting any wartime transmitter on the air is an interesting challenge for anyone. Finding the bits is just the start of it...

One way of cheating is to take a very modest transmitter - for instance the Wireless Set No.62, which struggles to put out even 1 watt on AM, and then add on a hefty linear amplifier with say 20dB of gain. You then get a system with a 100W of AM carrier, which if fully modulated is actually at the legal limit (400W PEP) for operation in the UK.


Richard

[Radio Wrangler]

The Collins TCS is reasonable.

If WWII isn't essential for the transmitter, how about an LG300? Plenty of power. And prices are reasonable. Were often used with AR88s and the like.

David

[M0FYA Andy]

After all the discussion of alternatives, I do have to agree with David when he says "I just think the iconic status of the 1155/1154 makes it special in my eyes, plus the undeniable beauty of both sets (chiefly the colourful '54)".

However that does mean to me that the whole system has to be assembled, with all the authentic peripheral units and not just the Tx and Rx. They can be found with patience, all I'm missing are the Londex relay and Resistor Unit in the DC input to the LT power unit.
Understanding the detail of the interconnection of the complete system and its interface with the other aircraft systems, for example the intercom and the TR1196, is all part of the interest to me.

I do have to confess to not having put power on the system, though, just too many priorities! One day, if I live long enough...

Andy

[trh01uk]

Two of the "authentic peripheral units" I would not advise using would be the original mains power units. They are about, and probably not quite as rare as some of the other peripherals.

The trouble with them is that they make extensive use of metal rectifiers. The chance of those still working is very low. They could be replaced with modern silicon rectifiers provided you know what you are doing. The difficulty here is that modern rectifiers are less lossy than the old MRs. So you are likely to get more volts than you really want. That can be adjusted by suitable modifications, but again you need to understand how to do the design work.


Richard

[G4YVM David]

Ok, well the waiting is over.There are lots of details that I am not going to make public but the nett result is that I now have an 1155/54 pair.

I'll post some photographs when I get the time together with my plans: firstly though, take the cases off. Both radios are very clean, dry (now) and free from any corrosion, mildew etc etc... you wouldn't say they've been dropped off from the QM but they are good.

It made me wonder though: how did the sets fare in use? I understand that on the long descents from altitude they'd be in use so no condensation would form, but sitting around Lincoln on those horrible winter days must have left them soaking! Or were they plugged in all the time and kept warm? (I recall we did this with the FFR Land Rovers in the sigs).

I appreciate everyone's input to this undertaking, and I hope to pick your brains as time goes on, but for now I am delighted that I have my childhood dream sitting in my shack. Actually, it seems to be occupying my shack with precious little space left for me.

David

[Radio Wrangler]

The rubber wouldn't have been crazed, they would have survived humidity and a bit of condensation fairly well without unwanted capillaries for to encourage the capillary effect.

David

[G4YVM David]

Thanks David

D

[Radio Wrangler]

Condensed water isn't very conductive and it's a lot more survive-able than you'd expect - but only for new equipment. For older stuff that's got dust and muck inside it, the condensate will dissolve ionic material out of the muck and will be quite conductive.

The R1155/T1154 in service, like their aircraft, had a short life expectancy. Most of the rigs were very new.

The bombers also didn't sit around much. They were wanted to be out there flattening places. They only got a rest when there was too much moonlight.

David

[G4YVM David]

Understood, but when weather clogged home or targets then they sat. Must have got damp, all aircraft do. I fly airliners and they HATE being sat in bad wx. It really upsets them. Airbus.

Anyway, my 54.is an M model.

D

[Radio Wrangler]

I know. I design bits for 'em. The small private stuff has it harder, being parked outside between weekends and getting several temperature cycles between each chance of driving out the moisture.. DO-160G has some fairly nasty treatments written into it. Fortunately, lower voltages help, but we're under pressure to make everything more efficient, so there's less heat even when things are running.

David

[G4YVM David]

I'm intrigued David, what do you design?

You say less heat...the avionics bay in the a 321would cook potatoes some days.
As for small ones, yes I've seen em dripping inside one day and baking the next. It's an environment amateur gear would shed tears at.

D

[G4YVM David]

Success so far...

The wireless sets have been fired up on receive: the 1155 is receiving just fine.

I have ascertained from the original owner (well, not original but the one before the one before me, the guy who converted it all to amateur / modern use) that he has made the Tx useable on topband, so it no longer works on 40m. This is a reversible mod and I might well put it back: I'd rather 40m cw that 160m AM. Well, I almost certainly will unless I get a sudden enthusiam for topband nets.

The Rx wiring is all fine too, it seems to have been rewired at some point in it's history.

Im waiting for a friend to come over and we shall test the HT prior to putting my new PA valves in.

D

[Reelman]

Good Luck David, after all that we have said I hope you enjoy your new kit!
Peter

[ian rose]

Originally Posted by trh01uk

I might add that if peripherals such as J-switch, DF loop, plugs/leads, morse key, microphone/headset, aerial current meter and intercom amp are all thrown in, plus a power supply that actually provides 1200V DC @ 200mA, 210V DC @ 110mA and 7V DC @ 13A are all thrown in... then £1300 may be a fair price, given that it will save you years of effort in rounding up all the hard to find bits.

My view is that, as you say, you have desired this set for many years you should snap it up [by all means make an offer] but snap it up anyway. you never know when you will get another opportunity and you will find much pleasure in seeking the peripherals and returning it to working condition.
If you end up paying a little too much ---- so what.
regards
Ian Rose

[HamishBoxer]

Just a point ,are the 2 x PT15 valves in the 1154 really duff I wonder?

[G4YVM David]

One certainly was, bits of glass and stuff knocking about the inside (not just the getter, far more) but the other one we THINK is okay. Anyway, we have left it in situ and will try it. Im hopeful for a spare valve.

I must say having this pair on my bench is rather like meeting a childhood hero...I almost cant quite believe it because I honestly thought I'd never get the opportunity to own such a thing. However, it's now knocking out Radio 4 Long Wave and whilst it is definitely LoFi, and my kids really cant see the point (does it text? Does do the internet?) Im just simply in heaven. Never have I heard audio so sweet.

I have found the mod that was done to put it on topband (a simple capacitor double up) and have reversed it: 40m is now back.

On the receiver most of it works: the filter, audio gain etc but Im not yet sure quite what they are doing...much learning to do.

And of course, as for actually loading up the tx to get RF...not a clue yet. Going to read now but any tips or trick most welcome. Interestingly, I can find NOTHING on youtube about using the transmitters...thats a big surprise...maybe vintage wireless owners have better things to do.

Ill post pics if people are really interested.

David