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Designing & Building a Vintage Style 3-valve TRF

How much does this interest you?

Very much
16
64%
Moderately
6
24%
Slightly
3
12%
Not the least bit interested
0
No votes
 
Total votes : 25

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Cathovisor » Thu Jun 16, 2016 8:57 pm

I wouldn't call nearly 1600 views a lack of interest... :aad

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Thu Jun 16, 2016 9:35 pm

Thanks for replies. Most of it was done by trial & error, guesswork, and experiment. But with so few members even bothering to vote, despite the high number of views, it didn't really feel like there was much interest. No doubt most of you are far more learned than me in such things, and I was looking forward to some sort of explanation as to the unusual tuning arrangement on V1 RF amplifier that I discovered purely by accident when I wired it incorectly and it worked far better than what I though was the correct way. :cch Also wondered about the noticeable improvement in performance when I connected the front aluminium strip to the frame of the tuning capacitor. I really can't see why it improved things, as the strip is not connected to anything else. I don't do radios all the time, it just surges up in me every few months, and I have to get it out of my system. There isn't a great deal more I can do with this one, apart from maybe make a nice wood-veneered cabinet for it. I was able to test my old vintage valves, sadly, about 75% of them either didn't work, or were low in emmission. It also serves as a tester for 1T4s and DL96s. As the resistors are in old glass fuses, I suppose I can experiment with different values without unsoldering any of the main circuitry. The whole thing did not cost much, as I already had all the bits & pieces, I didn't actually have to buy anything! Even the CR2032 grid bias battery was lying around, because when I changed the BIOS battery in my laptop, I could only find CR2032s in packs of 2 :aad Initially, I looked forward to some "lively" debate when I was told that I was going about it in "entirely the wrong way!" :aaj but nothing came of it!
Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Briancuff » Fri Jun 17, 2016 8:16 am

What a wonderful looking set you have created, love your models, from scratch. Like Aerodyn, I too have been under the weather for the last couple of months with my Prostate cancer so have not been actively active (if you see what I mean) but have followed your thread with interest - and voted!
Your little brass bridges remind me of a late 20s set I once had which used just such wiring with the bridges mimicking the schematic diagram.

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Fri Jun 17, 2016 10:47 am

Thanks, hope you are better soon! The brass bridges are slices of brass tube that I normally use for funnels on ship models. I cut a short length of tube, put it in the vice, and cut across it with a jeweller's saw, obtaining two perfect brass bridges!
Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Sat Jun 25, 2016 7:32 am

I have been silent on this for a while now, as I am writing a comprehensive download on how you can build this receiver. It will soon be available for a modest price. Here is the final blueprint that I completed this morning. I have left off the component values, as they will be included in the download, but most of you will probabaly be able to make an educated guess at them anyway!
Bob
Attachments
TRF Blueprint (Medium).jpg

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Fri Aug 05, 2016 5:33 pm

After completing this receiver, I began writing a constructional article on the building of it, including the circuit diagram, component valvues, and construction methods for the home-made components, layout, wiring etc. After a week, with just about zero discussion forthcoming here on VRAT, I lost interest and abandoned the project.
Recently, on looking at the receiver that has just been sitting here for several weeks, my enthusiasm revived somwhat, and I continued with the article.
At the time of writing, 1710 bst, 5th August, 2016, it stands at 18 pages, 42 illustrations and 3,815 words. The writing time so far, has occupied 5 1/2 hours, not including the preparation of all the images.
I hope to have it completed within the next few days. It will become available as an automatic download for a nominal sum, yet to be decided. I hope it will encourage modern-day vintage radio enthusiasts to "give it a go," but have no great hopes on this score.
I know my methods are rather "unconventional" to say the least, but that may appeal to some members.
Here is a sample page. (The caption should read "Capacitor and resistor mounts") This will be corrected in due course!
Bob
Attachments
Sample Page (Large).jpg
Sample page

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Lloyd » Fri Aug 05, 2016 7:29 pm

I will be interested in this! Pleased to hear you got your enthusiasm back, I think this is a great project. Something to have a go at in my new workshop when it's finally built!

Regards,
Lloyd.

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Fri Aug 05, 2016 7:42 pm

Lloyds,
Thanks for your interest. I am planning of £1.99, which is not too stressfull! :)
Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Sun Aug 07, 2016 7:52 pm

It is finally complete, at 30 pages with 67 images and 6,434 words. After the final checking tomorrow, I hope to publish by late morning. It has been a long, and weary task, and I am feeling quite fed up of it all now!
Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Mon Aug 08, 2016 12:38 pm

The download is now complete and online. It is available here:
http://payhip.com/b/KqJV
By clicking the link, you are not committed to purchase, but may read the synopsis. If you then wish to go ahead, a Paypal button is provided in the synopsis.
Initially, I had intended to make it available for £1.99, but on considering the matter, and all the work that went into producing it, I have decided on £2.99!
Here is a summary of the whole project, that may be viewed in the above thread displayed in VRAT.
Viewed 2,601 times.
POLL:
16 Very interested.
6 Moderately interested
3 Slightly interested
The design and construction work began on the 13th May, 2016, and the receiver was finally completed and working on the 25th June, 2016.
The download is 30 pages in length, with 67 images, mainly colour photographs, including the circuit diagram and component values. It has a total of 6,472 words and took 12 hours, 16 minutes to write. I reviewed and edited it 147 times before I finally decided that all was shipshape and Bristol fashion.
My methods are rather unorthodox, to say the least, but I make no apology for that. I hope that it will teach, and entertain those persons who wish to try their hand at something "different" in the field of radio construction methods of a long-gone era.
Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Fri Aug 12, 2016 8:16 am

I have now made a U-Tube presentation of the build, here:
https://youtu.be/GbarwQ-uRAI

Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Tue Aug 16, 2016 6:53 pm

On U Tube, it has now had 277 views, 3 likes, and 1 dislike. I guess this type of thing is too far off the beaten track, and apart from the large number of views here, has been something of a "damp squib!" I give up! :zx:
Going back to building ships! :aag
Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by sideband » Tue Aug 16, 2016 9:03 pm

I think the main problem is that building a radio has nothing like the interest that it would have done even 20 years ago. In these days of internet radio where you can receive almost any radio station from anywhere in the world at any time through your computer headphones, most people are just not going to bother building one. Very different in the 50's and 60's where there were sufficient people with an interest and something like this would have been very popular. Now we live in the throw away age, radio and television are considered 'mature' technologies and you can buy a cheap pocket radio for very little....probably lots less than this would cost and it would have FM stereo as standard......

Obviously there are exceptions and someone somewhere will find the whole thing fascinating. Whether they would actually want to build one themselves is another matter. Most people don't have the engineering skills of even 20 years ago and 'building something from scratch' is as alien to them as digital radio is to me! Now they might manage a kit if all the bits were supplied and if there was someone on the end of a help line if it didn't work or, better still, return the kit to for a full refund.....!

In a similar situation, we ran a 'minimalist radio' construction item a few years ago, myself and one other member scratched together some ideas and came up with simple superhet using a couple of easily obtainable valves with enough flexibility to use other types as available. The basic design worked well and initially there was a lot of interest. To my knowledge, only one member built the radio and housed it in a smart wooden cabinet.

As such, we never bothered to update, modify, improve....it just wasn't worth it.


It's a sign of the times I'm afraid.

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Tue Aug 16, 2016 9:15 pm

Yes, that about sums it up - pity really. I look back on my radio hobby schooldays with great affection. Bottlomless pit of army, airforce and navy surplus a low cost. Radio shops all over the place, fair number of schoolfriends building them. Even Practical Wireless magazine is a mere shadow of its former self. Radio Constructor gone a long time ago, but in my opinion superior in many ways to PW.
All gone!
Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Aerodyne » Wed Aug 17, 2016 10:12 am

Sideband is right- the world has changed and we have to accept it. It isn't just radio; I started out my working life in the printing trade (couldn't get into radio at age 15, long story) and was trained for six years as a stereotyper making metal printing plates. All that skill, useless now. Who prints with plates? No newspaper or magazine.
Car mechanics - how many would nowadays know how to fix a fault without recourse to the car's on-board computer? How many would be able to set points or repair a carburetter? Sure, there'll be some, especially the older hands, but there will become less and less of them. Then there's valve radio and TV. Or rather, there was. Now it is a big anachronism. All the hard-won skill and experience in valve technology no longer a means to earn even the most basic of livings, in our throwaway digital solid state society.
We could bemoan the loss of home construction (as I definitely do) and the loss too of the F.J. Camm 'Practical Wireless' packed with articles and fascinating adverts (and printed by stereo plate, by the way!) but we cannot stop the tide of change or we risk becoming ageing Canutes on the shifting sands of time's beach. We need to make a choice; to carry on regardless with our hobbies and ignore the digital age, or to understand that the world is actually indifferent to us and make the best of today's technology, always remembering with affection those seemingly golden days of the increasingly distant past.

Tony

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Wed Aug 17, 2016 11:37 am

All true, of course. I am now at the "tipping point," and about to "mothball" all my vintage radio stuff. If I see something sufficiently decrepit on a car boot sale, I may buy it for the fun or getting it going again, but that will be about all. Same with my seafaring profession, all the beautiful ships that I knew and sailed in are gone, except for one, (Passenger liner RMS St. Helena - extensively publicised on Google) and, despite being now 26-years-old, it is bordering on a bit "too modern" for my liking Re-opening my little shipyard today, where I can range up and down through the centuries and still have a demand for them. I spent a number of years in the Union-Castle Line as radio officer, hence my interest in radio. This is my model of the old Winchester Castle!
Bob
Attachments
Winchester Castle.jpg

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Katie Bush » Wed Aug 17, 2016 9:05 pm

Hi Bob,

Give it time on the "Toob" some videos need time to find an audience, and unless it's a three headed horse being ridden backwards through hoops of fire by a 90 year old granny with no legs, it ain't going to go 'viral'.

Also, I'd say ignore that one thumbs down - it's almost certainly some spotty faced little oick with no idea of what you're talking about (an internet troll) and will most definitely not reflect any real world interest.. Those little p****s are out to do just that - to put people off posting.. In American parlance, "haters".. In my own parlance, well, I'd be barred from the WWW if I posted my thoughts.... :zx:

Marion

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Thu Aug 18, 2016 6:54 am

The dislike on U Tube didn't bother me at all. I would have felt better if there had been 100 dislikes, because at least that would have shown something beyond the general apathy :aaj My methods of construction, servicing and attitude to theory and "whizz kids" :aal have come under severe critiscism all through my radio life both professional and hobby! I know my methods are generally frowned on, but I delight in the fact that they work! :thumb
Bob

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Aerodyne » Thu Aug 18, 2016 9:53 am

Marion is, as usual, spot-on, Bob. Some of my videos have been on You Tube for years and slowly build up viewings. Yours will do the same if you leave it to 'mature'.
As far as negatives and thumbs-down go, Marion is once again right. Anyone who gives your video a thumbs-down doesn't know what he or she is looking at. It makes you wonder why the twerp was looking in the first place. And you are not alone, oh no! One of my books received several five star recommendations on Amazon then one day I noticed the rating had dropped to (around) 4.75. Wondering why, I scanned down the review list. The last review gave me three out of five stars. The reason was stated in a single word: 'British!'. The buyer was American and hadn't taken enough care before buying or he would have realised the book was a British publication*. So, I was 'condemned' for being British, not for my writing skills.
That sums up the ignorance of a minority of people using the net. It's a big net - and a wide variety of fish!

Tony

* Despite being British, in general, American purchasers appear to like my books, thankfully.

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Thu Aug 18, 2016 12:45 pm

I have more success at writing books (not about radio) than designing and building vintage-style sets. Finally decided to reduce my hobby activities, and gain more space at the same time. I have just started dismantling a number of radios that I built over the past few years, and will be putting the individual components into small boxes where they will still be if I want to return to them at a future date. Wife has already noticed that things are getting tidier in my workroom! :aad
Here is the first batch on the "scrapping berth!"
Bob
Attachments
Homebrew radios (Medium).JPG

 
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Re: Designing & Building a Vintage Style 3-valve TRF

Post by Sparks » Sat Aug 20, 2016 4:50 pm

Since posting the above , I have been busy filleting the radios in the above image. Much to my surprise, I found this a very therapeutic and even enjoyable exercise. I am not doing it with the idea of either selling it all, or sending it to the tip, but to make it all fit into a much smaller space so that it will still be there should I wish to resume in the future. I am surprised at how much space this has recovered, and I have only dismantled seven or eight sets. I will be keeping the three-valve TRF as described above, and may even build a proper cabinet for it, thus changing it into a piece of acceptable, working, furniture. Several visitors have seen it, but only with the usual reaction of eyes glazing over in non-comprehension! :ccf Even the small round pot in the attached image contains in excess of £20 of assorted hardware in the form of brass nuts & bolts, double solder tags and insulated stand-off spacers. So I feel that I am achieving something without "bending" my brain designing and building them.
Bob
Attachments
Filleted radios (Large).JPG

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