AR88LF Original uses?

[PsychMan]

I've become quite fascinated by the range of AR88 series receivers lately. I understand the AR88LF (low frequency) version in particular was produced in Montreal for use in Europe during the 2nd World War. According to the excellent radioblvd.com site, the allies had a requirement for long wave.

Can anyone shed any light on why that was in particular? I'm aware that VLF was used for submarine comms, but this receiver doesn't quite go down that far. When enjoying vintage equipment its nice to imagine what it may have been used for originally

[Radio Wrangler]

There were (and still are) navigational beacons in that part of the spectrum.

I have one AR88D (bought recently) and a very early AR88 (no suffix!) that I bought in the middle sixties.

David

[PsychMan]

Good point David. Did they find their way on to many ships though? Hard to imagine that being much use as a desktop receiver?

Also, perhaps you can confirm, Would AR88Ds without the S-Meter, ever show "AR-88D" in the window, or simply "AR-88"?

As I understand it the only real difference is the presence of a case for "desktop" use.

Adam

[ms660]

Some of them were modified and used at Naval shore stations:

http://www.rnmuseumradarandcommunica...20RECEIVER.pdf

Lawrence.

[turretslug]

Originally Posted by PsychMan

Good point David. Did they find their way on to many ships though? Hard to imagine that being much use as a desktop receiver?

Also, perhaps you can confirm, Would AR88Ds without the S-Meter, ever show "AR-88D" in the window, or simply "AR-88"?

An AR88D, without S-meter, does indeed proclaim "AR88D" in the translucent window blanking plate, along with the frequency span. I've such a blanking plate here, it's tucked away in an envelope in the hope of slowing the photo-chemical darkening that afflicts these things...

There are anecdotal/apocryphal stories of AR88s finding their way on ships (and even tenuous tales of vehicle and airbourne use) but it's difficult to imagine that such a large and bulky piece of equipment would often have been used in anything other than a shore-based fixed installation. Of course, weight isn't much concern on a ship, but it still takes up volume compared to, say, a CR100, it's a notably deep chassis.

I'd wondered about the reason for the existence of the 'LF version, as the CR100 was produced in Britain in very large numbers with 60-420kHz LF coverage. Indeed, the AR88s noted stability and sensitivity at HF would have been pretty much irrelevant at these frequencies.

The AR88 is something of a classic, it happily married a number of what were then state-of-the-art techniques and developments but also kept a rein on production costs with straightforward mechanical construction. A good case of bang-for-buck.

[n_r_muir]

Hi

The AR88 and it's many variants was an excellent general purpose communications receiver of it's time. As well as many other base station uses in the Army, RAF and Y service the AR88 was used in Naval Shore Stations for the reception of Radio Teletype RTTY, They were usually rack mounted, in either dual or triple diversity configurations, along with the other items required for RTTY reception

[PsychMan]

Originally Posted by turretslug

An AR88D, without S-meter, does indeed proclaim "AR88D" in the translucent window blanking plate, along with the frequency span. I've such a blanking plate here, it's tucked away in an envelope in the hope of slowing the photo-chemical darkening that afflicts these things...

Thanks that's very interesting, I have not seen any online that display AR88D in that window, so I did wonder! I take it yours now has a meter installed?

The lettering would seem the only way to differentiate a "D" model from a later 88 housed in a case. I'd ask for a picture of yours but I don't suppose a flash would do the photo chemical darkening any favours!

[Radio Wrangler]

My AR88D says AR88D in on the bblanking piece fillling the S meter hole

My no-sufix AR88, from before the D/LF split doesn't clear up the matter because it has a real RCA matcing S meter! Quite rare!

David

[turretslug]

I'll dig out that plate, but I see what you mean about on-line piccies generally, having had a brief look. Maybe it was taken for granted that an AR88 was an AR88 , as it were, only ever covering 535kHz to 32MHz and they were simply labelled as such until the 'LF started to be produced when an obvious way of differentiating models was needed for non-technical folks such as equipment porters.

I think most 'D models would have been supplied in a case at least initially, but there's been around 75 years elapsing since for many sets to have been fitted in racks, removed again, put on the market with or without different cases..... Don't fall into the trap that some do of assuming that "D" means "diversity" with the implication of rack-mounting from the outset. Whilst all AR88s offer basic diversity capability, diversity-specific versions have a few basic tweaks to areas such as AVC interfacing and ISTR that they were described as "F" variant. (Not sure whether this was official or unofficial). As for the "D" designation- who knows for sure....? It's a bit like the origin of "OK"- everyone has a differing explanation and everyone is adamant that theirs is the right one....

[G3VKM_Roger]

Back in the late 70s I had cause to visit RAF Garth Ness, a Loran station near to Sumburgh airport in Shetland. The station was on care and maintenance and was unmanned but I was shown around by a local caretaker and saw several rack-mount AR88s. I can't recall the type at this distance in time but Loran A worked on the high end of the 160m band and a later version (C?) on 100kHz.

Roger/G3VKM

[Radio Wrangler]

The matter of cabinets for AR88s is interesting.

It seems that the majority of receivers were rack mounted, yet nearly all appearing on the market in the fifties and sixties had original RCA cabinets with the hinged hatch in the top.The rack-mount applications used separate panels with the S-meters collected together for easy comparison, so the vast majority of AR88s having no meter fits with this, though there was a general shortage of meter movements at the time of manufacture.

I suspect that the receivers came in cabinets, and that the cabinets were stored somewhere, to be brought out of store when hordes of AR88s were finally sold-off.

David

[ian rose]

Some time ago on a web site devoted to AR88's I saw a photo of operators at, I think, Bletchley Park operating a number of the receivers bench mounted in cabinets.

[russell_w_b]

Rack-mounted AR88s, along with RA-17s were used at the BBC Receiving Station, Tatsfield at one time. Don't know about the LF variant though.

http://www.bbceng.info/Operations/Re.../tatsfield.htm

[HamishBoxer]

I thought until now no one had mentioned Bletchley park. Mine as far as I know has an original S meter and a cabinet.

[trh01uk]

When you say "original S-meter", was there ever an AR-88 with an S-meter fitted during factory production?

The only fitting of an S-meter that I have on record is an RAF modification to fit one, which produced the Air Ministry Type R.1556 receiver.

Richard

[PsychMan]

According to the wonderful radioblvd.com site, some ar88s did come with factory fitted s-meters, but very few indeed. I think most we see now were fitted by radio enthusiasts post war, or in service as you say by the RAF.

[PsychMan]

Thanks all for the input, its been interesting.

My interest in the LF lately has been due to me acquiring one a little while ago. Or at least it looked like one - It has a plastic panel that's been cut so you can see the model number ar88lf, but it has an s-meter behind it.

What is odd is it has a "Phone" mode and "BFO" instead of the "REC" options on the front panel. According to radioblvd, this would make it a CR91 made at the Camden plant. the CR91 being a late WW2 Camden built version of the LF. So either its an in-between model, or someone changed the front panel or meter panel at some stage. Sadly the serial looks stamped in ink and only one number is legible. Another plate was mounted at the rear of the chassis but has been removed at some point. As I restore it I may find more, currently the audio output is working, but no radio just yet.

There is a notice on the chassis to indicate it had the moisture and anti-fungal coating July 1944, which I imagine would have been a factory treatment and would indicate when it was built.

The panel does make it an interesting piece, its black wrinkle finish like other AR88s, not the blue or grey seen on CR91A models. Has anyone here come across black CR-91s on their travels?

[Lavaldb]

We used the 88LF for spectrum surveillance in Quebec in the late fifties to monitor the weather traffic from the far North stations. Often also used during the graveyard shifts for listening to WPTR music. The pair of 6L6's rendered superb audio.

[Herald1360]

Pair of 6L6s?

One lonely 6K6 usually.

AR88GT?

[G4XWDJim]

Probably the Hallicrafters S27 which had a pair of 6v6s in the output stage and did sound good with the controllable negative feedback circuitry.

Jim