What about this then…

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In the days of the 1970’s as an apprentice TV and Radio Technician at Telefusion (about 1974) I worked in a small unit in Cobden Mill mending radios and cassette recorders and other small items. The miners were on strike and we had a three day week. Trouble was that you could mend transistor radios without mains power, so we bought a load of batteries and carried on working with our coats on! It was great fun really!

Around that time I worked with some more apprentices, Ian Harrison, Bhad Govan and Jim Hulton. Ian was quite keen on amateur radio and one evening we went to see a well known amateur radio voice on 80m who’s callsign was G3MCR (more about this later)

One day I was repairing a cheap transistor radio that covered all the Short Wave bands including 160m and after replacing a component and re-aligning the radio using a Heathkit Signal Generator, I decided to have a listen on 160m. Guess what…there was Alf, G3HRV in Walkden about two miles up the road. After listening to his QSO with a room full of apprentices I thought it might be good idea to try and contact him using the Heathkit Signal Generator!!

A bit of a long shot, but by keying the aerial (a TV aerial that went all the way up the side of Cobden Mill) I thought it would be worth a try. I called Alf in CW and….he came back….i’ve never seen a room full of apprentices so astounded! We completed a QSO in CW with about a milliwatt of signal!

This was one of my most original contacts ever, and yes…I put it in the logbook!

Alf was a great guy, I went to see him a few times when I worked in Walkden. I would often listen to him talking on 160m with Ralph, G3WWZ.

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Flying Spot Scanners

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Watch out….there’s a 5FP7 about!

I thought it might be interesting to post this on the blog…an email from John Stratham who went school at the same time as Neil G3ZPL.

While Googling during a quiet time at work, I came across your site which fired off some happy memories.
As a youngster at Bolton School I was always amazed by the skills of Neil Richardson G3ZPL who ran the
Radio Society. I clearly remember him working on TV using a photo-multiplier tube he’d aquired from somewhere. I have not heard anything of him since he left school and often wondered what became of him.

Hi John,

Thanks for your message, always nice to hear about someone who has happy memories!
When you were at Bolton School I was at Deane Grammar School where we also had a ‘kind of’ Radio Club at lunchtimes. Our Physics teacher Mr Bristow, was also a licenced radio amateur, but he never went on the air!

Neil and myself got our licences about the same time (1970/1) and used to talk for hours on 160m and later 2m and 70cm bands setting up cross-band contacts which allowed us to chat like being on the phone. One of the best projects that we did together was Amateur Television. Neil had a photo-multiplier tube and a 5FP7 flying spot scanner and this allowed still images to be transmitted over the 70cm band to my receivers. Neil worked out a really clever way of not having to send ‘sync pulses’ to lock the images…we used the BBC’s ‘sync pulses’ by tapping them off another TV receiver. Dead clever! Neil had such innovative ideas, great times were had!

After leaving school, Neil went to Cambridge University and took a Degree in Engineering, then later completed a Phd in Engineering at Cambridge. Neil then got married to Christine (also from Cambridge) and then moved to Palo Alto in California and worked for a large company over there. He now travels around the world and is president of another company over there in Palo Alto. Neil and Christine have three children and as far as I know they are still in Palo Alto. Neil keeps in touch, but I don’t think he has been to Bolton for quite a long time now.

As for me John…i’m a Primary School teacher in Bolton and love my job!

A lot of memories here! I remember the famous 5FP7, never got one myself, but I will never forget the smiley face that Neil painted on the front of the tube then transmitted via the photo-multipier tube. This was the first image that I received over 70cm, I thought it was hilarious…a big smiley face filling the screen! The 5FP7 was a long duration device, the screen would continue to glow long after it was turned off, so the smiley face would glow under the bed all night….scary!

I managed to obtain a couple of high quality photomultiplier tubes that came from the Winter Hill transmitter supplied by my Uncle who worked there. These devices provided the ‘Test Card’ from the ITV Transmitter. I never did get these devices working!

Partygram!

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So much for the 6BW6…along came…Solid State Technology! Yes! Transistors!

By this time I was working as an Apprentice at Telefusion Ltd on the front line of Technology. So my next project was to improve the original Stereo amplifier and bring in Solid State Devices (Transistors) My friend Neil had just built a slimline amplifier based on an amplifier in Practical Wireless, the Partygram.

The Partygram was a Mono Amplifier that used two high power transistors (AD161 and AD162) in Push-Pull Mode to give an output of 10 watts rms. Two of these amplifiers built in the same box would give high quality stereo! I was dead impressed with Neil’s Amp, so I set about building one myself. I managed to obtain most of the parts from work, but the most expensive item was the mains transformer. The drivers and pre-amps used BC108’s and equivalent PNP devices. I built a case from aluminium and my Dad built a wooden surround, all the controls were mounted on the front. This was a superb project, we could have audio separates (Amplifier, Deck, Speakers) and was used at home and later when I got married right up until about 1980 with a pair of wall mounted Bush Denon Speakers (actually Warfedales)

Later, I used the case of the amp to house another amplifier, a FET 100 watt disco amp from Maplin which to this day is still used…in fact I used it yesterday at school for the Christmas Disco!

I still have an original copy of Practical Wireless with the Partygram circuit and details, how sad am I?

What’s a 6BW6?

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Well, here it is the famous 6BW6 valve!

What’s a valve? you Digital Natives may ask… Click HERE!

This versatile little beast could produce around 10 watts at Audio Frequencies and great for my first attempt at a stereo amplifier.

Our ‘record player’ built by my Dad, sat in the corner of the front room with a speaker built in the front. It sounded nice!
Hi-Fi was the ‘in thing’ back in 1969 and records and LP’s were now going STEREO so my Dad and I decided that we would build a stereo record player!
The original amplifier in the box came from an old radio that my Dad had used as an amplifier, not bad kit really, 6V6 valve amp provided a fair old sound. I decided at first to strip down the amp and use the chassis to build the new one…a bit of task really as it was my first project with valves! After a lot of drilling, filing and wiring the new stereo amp began to take shape, meanwhile, Dad was building the new wooden speaker cabinets…tall, slim and dark.
OK…I had a few teething problems with the amp, the pre-amp needed to be quite sensitive because we planned to have a deck with Magnetic Cartridges and this caused a lot of instability in the amp, so much so that the poor 6BW6 would glow red!!

Bought the record deck from Barry, G3WIS, a real piece of engineering, super heavy and stable complete with Magnetic Cartridge.

At last we were all ready to hear STEREO for the first time. To test the equipment we used a record that was made to demonstrate the effects of STEREO…I can still hear it now…”June is bursting out all over” and the train whizzing from one speaker to the other! I had just bought ” Bridge over troubled water” and this sounded great on the new system.

Hi-Fi at last, thanks to a couple of 6BW6 valves!

Later, the 6BW6 along with the 5763 and EL84 valves gave me the power to build transmitters that could transmit Radio Frequencies 160m and 80m!

Morse Code

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This is the very same Morse Key in the photo taken by Dad of me when I was 17! It came originally from M. Dzubias in a big green box for about 50p! I still use it!

Today, Morse Code is simply ‘past it’s user date’ , slow, inefficient and what the hell is it anyway? Children can ‘text’ on their mobile phones, but have never heard of Morse Code!
Well, here is my story from the days when Morse Code was the tried and tested way of communicating in even the most difficult environments, when radio operators on ships used Morse Code as part of their everyday life and Radio Amateurs had to learn it (like it or not) to gain a Class A licence.

In 1971 I passed my Radio Amateur Exam in May, my next target was to learn Morse Code at 12 Words Per Minute in order to pass my Morse Test to achieve my Class A licence.
George (G3ZQS) was an ex navy operator, he taught me everything I know about learning Morse. He would come around to my house in his slippers and teach me the G3ZQS way of learning morse. George was a real character, did so much to inspire me to go for it and also to bring so much pleasure to others learning the code. George made his own tapes, using the ‘George method’ I was able to learn Morse Code up to 20 WPM before taking my test. (A real acheivment for me at the age of 16!) George’s methos involved grouping letters together with similar sounds and rhythms (Q – God save the Queen – dah dah dit dah)

It worked for me!

Soon I was on my way to the Liver Buildings in Liverpool with my Dad to take my Morse Test. I even had to get time off work for this. The day itself I can remember like yesterday, we got lost in Liverpool trying to find our way and asked a man near the Docks, gave us directions and explained how the Dockers were all on strike!
In the Liver Building we walked up several flights of stairs to the place where the test was to held. I was shown into a room with several different Morse Keys to choose from, I chose the shiny brass one, and asked to practice for a bit. Then I had to listen to a passage of text in Morse Code and write it down, following that I had to send a passage in Morse Code. I was allowed three errors! Scary stuff!

Well…I passed!

I could at last send for my Class A licence!

A word about George, G3ZQS:

  • Can listen to morse like we listen to words!
  • Can send Morse Code on a broken hacksaw blade at 60WPM!
  • Can send and receive Morse Code at 60 WPM after drinking several brown ales!
  • Can drive a big car with his slippers on!

A man of many talents!

So now, in the digital world where children, grown ups and digital natives send text messages daily, I have one advantage….

Text messaging is really Morse Code….and I can send it faster than they can text it!!

NEV CAM

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You have heard of a WebCam?

Well, back in the early 70’s I did some experimenting with Amateur Television (more about this in a later post) Along came Barry (G3WIS) and offered me this small and compact NEV Camera with a ‘C’ Mount lens for 10 quid! I couldn’t resist so I bought it. It was a super camera, 405 lines, Black and White and good definition. The camera was used to transmit true 405 line television pictures on 70cm between my friend Neil and myself. This was unheard of at the time…we were pioneers! (and analogue natives)

The camera itself had two printed circuit boards stacked one above the other. The circuit used quite old and noisy transistors, so I decided to rebuilt the camera by modifying the circuit to include BC type transistors and make new printed circuit boards from scratch. The camera actually worked, and worked well! The only problem was the connectors on the edge of the boards which became a bit intermittent.

Im have never been able to find out about the original camera from the Internet, but it was certainly a nifty little camera for it’s time. I can’t remember what happened to the camera, in the days of 625 lines the cam became obsolesent and disappeared forever. Maybe someone, somewhere, has one of these in a museum!

Here is classic link for the old magazines!

Modern Radio

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My first memories of Modern Radio bring cold, dark Saturday afternoons, long queues and the cigar smoke! Back in 1967 the shop counter was a small, crowded area with the man with the cigar (I always thought he must be rich!) and the lady with the glasses. I wanted to be served by the lady because she was always nice to me and helpful. Sometimes Diane (the daughter) would serve to help out. I always remember waiting…and waiting, men in front with handfulls of valves wanting to be tested on their renowned valve tester, long lists of components and technical sounding questions. I was about 13 at the time, somehow I didn’t fit, I came with pocket money to spend, not a pro! I can still picture the cabinet on the wall on the left hand side full of valve boxes that never seemed to move.
Modern Radio was handy, my school bus stopped right across the road, so I would call in on my way home from school, sometimes just to look in the window. Compared to the shop on Deane Rd, prices were not cheap and God forbid if you had to order something which came from RadioSpares! When I built my first Topband Transmitter I needed a fairly sturdy tuning capacitor which had to be ordered, when I came the price was devastating! I really couldn’t afford to buy it and had to spend about three weeks pocket money to pay for it.

Modern Radio is an institution! I can’t imagine the shop ever closing. I still call in to buy my bits and I love the same atmosphere when I walk in the door. Diane runs the shop now with her daughters and you can still get those components. I pass Modern Radio a lot and still enjoy parking and spending time looking in the window.