Alan Cavender G4FNM in Stocksfield, Northumberland wants a KW160 ‘one-sixty’ transmitter to go with his Eddystone 730/4 receiver. If you can help Alan then please contact him at – alcav@yahoo.com
Clive Walker M1MST, near Ludlow has an Eddystone 730/1A for sale. Clive says he has had this a long time and it is working (PLEASE NOTE THE SPEAKER IS NOT INCLUDED IN THE SALE). The mains is wired directly in to the rear of the radio. Internally the radio looks OK and still has the original trimmer and spare fuses.
It will be collection only from SY8 4ND near Ludlow. No post on this one. Clive is looking for £150 for this receiver. If you are interested then contact Clive direct on e mail clive.walker5@btopenworld.com
Sian and Roger Digby contacted me about some radio parts that belonged to Roger’s grandfather who passed away some 60 years ago and who was a keen radio enthusiast and had been the owner of an Eddystone Receiver which Roger remembers his grandfather using to listen to overseas shortwave broadcasts when he was a boy. Roger kept the set (he can’t recall the model number) for some 40 years after his grandfather’s death and finally passed it on to another radio enthusiast who had helped his son with a motorbike problem. Roger’s wife Sian had found a box of radio parts belonging to the grandfather when sorting through some cupboards in their garage. They passed them on to me in the hope that they might find a new home with someone in the Eddystone User Group. Here is a list:
If you see anything of interest then contact Chris G0EYO EUG Admin on g0eyo@blueyonder.co.uk.
Simon M5POO in Corbridge, Northumberland is looking for a Multi Wave Switched Coil Unit originally made around 1935, for a little project he is working on. The one he is specifically after is the Cat. No. 961 option with 260/600 metres as the lowest frequency option. If anyone have one, either used or unused that they would be happy to part with please drop Simon a line at simon(at)m5poo(dot)co(dot)uk.
Interesting anecdote from EUGer Roger Tricket about his lifetimes experience with his much loved Eddystone EC10 receiver
In 1969 I was posted to a position in New Guinea, so took delivery in Melbourne early Jan 1970 of a new Eddystone EC 10 Serial 6605. It has been to New Guinea, Indonesia, Saudi Arabia, England, Thailand and a number of locations in my home country, Australia.
EC10 above ICom 8500
It has been turned on continuously since new apart from periods in transit, so now in 2024 it seems it would have been on for all of about 50 years of its 54 year life (2024).
Still used every day for a shortwave broadcast I like and as in all those years when not listening, I turned down the audio, but leave the set running. It has generally been fed from 20 – 30 ft aerials, sometimes thru a mini aerial tuner. Now wire aerial through 1 to 1 toroid transformer into coax to the set. (note the station closed about 2020). Now in general use but always on tuned to WWV.
WWV freq on dial
Alterations – replaced all electrolytic capacitors about 2015; the agc line cap now uses a bipolar cap as there was a question relating to the circuit polarity, it works better now. When adjusting the mixer trimmer with metal shaft screwdriver, it shorted and killed the mixer transistor, which has been replaced from a stock of replacements I keep ( these have the leads wound together in attempt to avoid the dreaded whiskers ).
Rear view with power and antenna connections
The power supply is a 9v plug pack and fed to an 8v voltage stabiliser built into the case about 2016. However for some 30 years it was fed with voltages from various sources 6v to 12v and even a standard mini 9v battery, on which it will run for several hours. Note: set runs positive to earth so cannot use common power supply with other equipment – the plug pack has negative to earth so reversal is done in the voltage stabiliser which uses feed in from an isolated input plug; see pic.
The aerial terminal was replaced with a coax fitting ( for 50 Ohm line ) which feeds an internally mounted mini toroid balun – 50 to 75 Ohms so the twin diodes are removed. The BFO injection Capacitor was increased to 3PF. As a signal strength meter I use a 100 Microamp meter direct into the audio out socket as this carries the AGC voltage in the original wiring from the factory.
Original box and instructions
Compared to a modern Icom R8500 receiver it does a very credible job, though frequency drifts notoriously with daily temperature changes!
It is now 2024 and I am in my mid 80s so with luck it will outlast its owner………
Compared to a modern Icom R8500 receiver it does a very credible job, though frequency drifts notoriously with daily temperature changes! It is now 2024 and I am in my mid 80s so with luck it will outlast its owner……
Interesting note of relevance – Nasa used these same germanium transistors in early space exploration and it has been found “whiskers” grow in the RF metal case transistors and kill them. There is a document available where Nasa explores this subject. Hence this set needs to run continuously which seems to avoid the problem.
Note – In 2021 the on off power switch in the RF gain control failed and there is now a mini switch on the rear.
Roger Trickett
Way back in September 2023 Chris G0EYO (our beloved mentor) put out a request from Jon MI6XGZ to see if anybody would repair his deceased father’s (callsign GI3ZX) S640 as he would like it to be working so he could use it for old times sake. As MI6XGZ obviously lives in N.I. and me living just over the water in Southern Scotland, I responded and arrangements were made for a friend visiting MI6XGZ living in Central Scotland to drop it off as he passed the door from the Stranraer ferry. It was duly dropped off in January and put in the workshop for attention.
Now MI6XGZ’s deceased father, Desmond, has an interesting history in his own right. Licensed well before 1939 he was conscripted into the VI service at the start of WW2 and formally moved to the RSS secret listening station in N.I. GILNAHIRK where he stayed until de-listed in 1947. He passed away in 1984 and Jon MI6XGZ kindly scanned the final pages of his father’s log book from 1937 showing who was on the air then and the final entry before receiving official orders to go QRT. The log pages are shown below.
As soon as the set was received the bench was cleared and the transport box was opened and yes there was an Eddystone S640. However, it had a long large umbilical cord coming out the back with an industrial size plug on the end. Ok, could be a link to a transmitter or something.
Lifted it onto the bench and the front was from a 640 but looked very modified and the obvious give away should have been a microphone socket on the front panel!!. Eventually opening the lid (seized due to rust) sitting looking up at me was a pair of TT21 PA valves. Strange???
Both tuning capacitors had been removed and a small 30pf variable installed in their place. The coil pack instead of having the two valves (EF39 and 6K8) had 7 B9A valves and the I.F panel had its top
chassis cut away and removed and in its place was a series of relays and what looked like filters of some sort or other.
This S640 was obviously a transmitter built into a 640 case and chassis. The construction was a masterpiece of ingenuity to squeeze a 13 valve transmitter into a 640 case. So why the umbilical cord then?. Was this for the power supply and modulator for AM? Could be.
Removing it from the case caused more intrigue. The coil pack had been stripped of all its previous coils and poking up were a couple of crystals 8998 and 9001khz. Turning the set back over and cleaning a filthy small box revealed a crystal SSB filter at 9MHz so we must have an SSB transmitter,
It gets more amazing! There’s a loudspeaker on the back of the front panel, chasing the modules through not only do we have a transmitter made out of a 640 but we also have a receiver built in as well. A quick look about confirms that we have a 80/20metre SSB transceiver built into and on a S640 chassis and case.
I decided not to put power onto it as; a) I would have had to build a power unit and b) as it must be over 50, probably 60 years old, heavens knows what would have blown up!!.
So there you have it. Not only a wonderful piece of engineering expertise but craftsmanship as well. Pity we don’t have people like GI3ZX about these days when it’s so easy to buy a transceiver. Hope you have enjoyed this little story.
Roy GM4VKI
Phil G4OBK in Pickering, North Yorkshire is helping the family of Malcolm G3KEV of Scarborough who went Silent Key last month at the age of 87 dispose of his amateur radio equipment gear. The money raised is going to the Yorkshire Air Ambulance Service and Phil is on his way to raising at least £2000 from the sale of Malcolm’s gear for the charity.
Phil is offering an Edometer S902 Mk2 in excellent condition, complete with carry box, the seven coils and the original manual (see pic – more photos are available from Phil). Phil has checked to see that the PP3 battery had previously been removed and that there was no contamination inside the unit.
He fitted a new PP3 and checked that the unit does function as a signal generator. He also checked that the fixed 1000 Hz audio tone output was available on the right-hand side headphone socket but he hasn’t tested the other unit functions.
Bearing in mind that the proceeds are going to charity, Phil is inviting bids for this item and has put a deadline of Saturday November 4th for anyone wishing to make an offer for this historic Eddystone Item, without which no Eddystone collection would be complete. If you are interested in making an offer or wish for more details contact Phil by e mail on cq@yorkshirewalker.co.uk UK delivery only unfortunately. Shipping can be arranged via Royal Mail 48 tracked for £7 but collection from Pickering is also acceptable.
Those of you who have read Victor’s previous articles, especially the one on his Eddystone 888A restoration, will know that they make very interesting and informative reading. Victor is a man who knows his way around RF circuits and has a passion for getting the best out of his receivers which he uses on a daily basis for shortwave listening. Victor has now written up his work in refurbishing an EA12 so that he could get the best performance out of it. A fascinating read and I am sure many readers will enjoy and benefit from his experiences and expertise. You will find the article in the Restoration folder but you can download if from here.
Eric White in Worcestershire UK is looking for an Eddystone EC10 Receiver (1963/1965) in good condition, although can be none working. If you can help Eric please contact him via email eewhite359@btinternet.com
Dean Preziosi of Shirley, Massachusetts, USA is seeking a left frame panel and disc set cover for an Eddystone 958/3. He has included a picture of the receiver showing the left side minus the two pieces. Please contact him at
tonym4704@gmail.com if you can help out.
