Vintage GEC Two Way Radio

[jomac_uk]

I recently spotted an early 1960's GEC low band transceiver on eBay and searched for further information without any success.

I looked originally under just GEC which took me to the 660 and 600 series radios which this isn't. I widened the search to GEC-AEI and found nothing new. I'm aware that Dymar made sets for GEC and again looking through the different models, I don't see anything even close.

The radio has strong overtones of the PYE Bantam but it isn't that one either.

I did end up buying it for pennies because to me its a little bit of an enigma and begs to be restored.

Can anyone shed any light on this?

TIA

[Aub]

It looks a bit like the sets that GEC mobile radio made at the Spon Street factory in Coventry, except I think they were a bit smaller.

Hope you get it going. Is it AM ?

Cheers
Aub

[jomac_uk]

Hi Aub,
normally I'm pretty good in tracking down equipment such as this, but this time Ive drawn a complete blank. I spotted this on Youtube and the lack of information made me curious so i bought it for pennies. It's not arrived yet but looking close someone has written the TX/RX frequency on the aluminium panel, on the rear is a sticker and looking close i think i can see the letters FM, but looking at the internals there is either a transformer which would suggest its AM unless the transformer is a choke. I'm a licenced radio ham and thought it would be nice to modify this for the 4 Metre band at 72 MHz

[Aub]

Yes that would be a nice project to modify it. I see the crystal filter was made in Salford. I wonder if there any history on the web about that company?

I wonder what the batteries were. Perhaps 8 AA cells, to make 12 volts?

Aub

[jomac_uk]

In my extensive search trying to track down this radio, i did find out that Salford Electrical Industries were purchased by GEC in 1958. GEC then transferred its crystal filter manufacturing from their Manchester factory to Salford in the same year. SEI ceased production of filters in 1962, so unless GEC had massive stocks of filters that would put the age of this set around about this time. I havent received the set yet but when i do, i will go over it with a fine tooth comb. A couple of things are bugging me however, I mentioned a similarity to PYE earlier on, the components look a little too modern to be very early 1960's another thing is the loudspeaker, it has the number 7322 on it. If we follow date codes usually found on components, this would suggest week 22 of 1973, so either its a replacement or a red herring, the components are far too old to be found in a radio like this.

I see the battery space but i'm not sure about it being 12v if it used AA type batteries, using nearby components as a guide, it might be a bit tight, also look under the foam, there is a rib or moulding to suggest something in a pair may have been used, 6v perhaps. If this radio is circa 1960.the set looks as if it slides into a mount with rear connections. There were still quite few cars around that had 5 volt batteries, just a thought?

[G6Tanuki]

Originally Posted by Aub

I wonder what the batteries were. Perhaps 8 AA cells, to make 12 volts?

Aub

I suspect it would have used rechargeables: back in the 60s and 70s the typical rechargeables were German-made "DEAC" Nicad cells that could be assembled into a range of different layouts - they were either cylindrical like an AA or C cell but slightly-differently-sized, or they were flat like the current 'coin cells' used in keyfobs, watches etc but about 6x the thickness.

DEAC cells were often assembled into battery-packs using blue or yellow transparent heatshrink-sleeving.

Also worth noting that quite a few early semiconductor two-way radios used surprisingly high voltages - some of the Pye stuff used 18V as the transmitter 'HT' rail and the car-charger/adapter units incorporated a step-up inverter [which could also deal with the whole positive- or negative-earth issue which was around in the 60s]

[AC/HL]

It may be the removable receiver from an RC600T/R, as there is no microphone socket.

[jomac_uk]

Well we seem to be getting one step closer. I posted the above question in one of my ham groups on Facebook and one guy posted the following...."I think it’s the receiver section of a P band AM transceiver made by GEC for the Home Office, and was designed to be unplugged from the larger dash mounted set, and used portable. It had a small Deac battery to power it, charged from the vehicle supply"

[Radio Wrangler]

The crystal filter made in Salford would be from Salford Electrical Instruments Ltd, a GEC subsidiary.

They were very competent crystal and filter makers, with Dave Standring running the department when I knew it. On the same site (Times Mill in Heywood Lancs, despite their name!) they made polystyrene and other dielectric capacitors as well as ferrites and powdered metal magnetic cores. In latter years their big earner were RF/DC multiplexer boxers to use the rear window heater as a car radio antenna and had the contract for these from Ford. Outside the mill building was a large gasometer where they kept hydrogen for reducing oxides for the powdered metal cores.

All gone now. A supermarket sits where the old mill and gasometer stood.

When I designed a little directional power meter for the G-QRP club I thought it appropriate to use ferrite cores made within a mile of George Dobbs' vicarage.

David

[Cruisin Marine]

I only worked on the GEC 660, 665 (AM) and the 625 (FM) which were all PMR mobiles. Apart from the same knobs it bears little resemblance from memory.
Having said that, it is more like the square shaped 660 than the later rounded shaped sets.

[Aub]

I was getting mixed up with ones I remember seeing, a couple of years ago, in an advert from Wireless World from the early seventies, I think. Those units, to me, resembled the old Trio TR2200 Two metre transceiver from the seventies - nice looking, in a leather carry case with a telescopic aerial. I could probably find the copy of Wireless World concerned if I searched on the Radio history site. Only of accedemic interest, of course, in this case.

Sounds like you're getting close though.

73

Aub

[Refugee]

I have got a slightly more sturdy one from that period. It has an external speaker.
It goes out just below the FM broadcast band according to the counter on the one occasion I keyed it up. Some of the filter boxes look ITT.

[jomac_uk]

Originally Posted by Refugee

I have got a slightly more sturdy one from that period. It has an external speaker.
It goes out just below the FM broadcast band according to the counter on the one occasion I keyed it up. Some of the filter boxes look ITT.

Could you confirm the actual model number and where i migh find a circuit diagram for the RX side at least?

[jomac_uk]

Originally Posted by Aub

I was getting mixed up with ones I remember seeing, a couple of years ago, in an advert from Wireless World from the early seventies, I think. Those units, to me, resembled the old Trio TR2200 Two metre transceiver from the seventies - nice looking, in a leather carry case with a telescopic aerial. I could probably find the copy of Wireless World concerned if I searched on the Radio history site. Only of accedemic interest, of course, in this case.

Sounds like you're getting close though.

73

Aub

Yes, I clearly remember the styles back then, my favourite by far is the Yaesu FT290 Mk1 and i have a group covering these on FB.

G8TDU

[jomac_uk]

Originally Posted by Cruisin Marine

I only worked on the GEC 660, 665 (AM) and the 625 (FM) which were all PMR mobiles. Apart from the same knobs it bears little resemblance from memory.
Having said that, it is more like the square shaped 660 than the later rounded shaped sets.

Why are these radio's hard to find info on? Ive spent considerable time over the last three days searching for GEC info, ive even looked at Graces Guide to search subsidiaries of GEC. The closest ive managed to get is plenty of general info on the 660, a brief mention of the 602 and one page on the 665.

[jomac_uk]

If i can get my hands on the schematic/circuit diagram, it would be nice to convert this to an AM/FM receiver to cover 6 Metres, my favourite band.

G8TDU

[Restoration73]

It is possible they are some development samples not made in quantity.

It is notable that in this era Marconi Marine (a GEC company) bought the Pye FM Bantam and just applied their badge to it. (HP1FM for 156MHz band)

[Refugee]

Originally Posted by jomac_uk

Could you confirm the actual model number and where i migh find a circuit diagram for the RX side at least?

The model number went missing with the cover unless it is still about.
I just have the set in deep storage.
It looks quite AM without going deeper.
It measured 87.something Mhz all those years ago with my counter.
Only one of the four crystal pairs is populated.

[jomac_uk]

To me it looks very much like a Dymar set. During my searches i did see several GEC radio's with Dymar microphones, they just looked too exact to be a coincidence, but looking at vintage Dymar radio's didnt show anything remotely close to mine.

The holy grail for me now is to track down a schematic for this radio, but without an exact model number, its going to be a long search.

[jomac_uk]

Originally Posted by Restoration73

It is possible they are some development samples not made in quantity.

It is notable that in this era Marconi Marine (a GEC company) bought the Pye FM Bantam and just applied their badge to it. (HP1FM for 156MHz band)

This was my first thoughts when i couldn't find anything on my unit. The layout is very similar to the Bantam, but after comparing interior pics of the Bantam and mine, that's where the similarities ended, I did mention this in my opening post.