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5th Jul 2020, 6:29 am | #1 |
Diode
Join Date: Nov 2016
Location: Seattle, Washington State, USA.
Posts: 7
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French Valve Tester project (Lampemètre FC2010)
Hi All,
Discovered this valve tester project while browsing around the web a few days ago. Curious if anyone here might have built it? Originally published in Radiofil Magazine Issue № 41 in Nov/Dec 2010. Unfortunately, all the documentation I've found during subsequent searching has all been in French. Thinking to get it professionally translated as it looks to be an interesting project. There's a fair amount of discussion about it here (again, all in French). Decided to have a go at building up the Sussex Valve Tester in the next few weeks, perhaps the FC2010 would be next? Regards, Greg |
6th Jul 2020, 3:49 am | #2 |
Heptode
Join Date: May 2005
Location: Adelaide, South Australia
Posts: 541
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Re: French Valve Tester project (Lampemètre FC2010)
Making a homebrew valve tester is a bit of a job, while solid state power supplies etc make it possible to make the electronics compact the valve socket switching can be a bit of a headache to make compact, a few banks of rotary switches take up a bit of room, I searched for ages for interlocking push button switches - the plan was 9 rows of 10 push buttons one row for each valve pin, I settled for thumbwheel switches when I saw some at a reasonable price, that banana pin/matrix setup looks quite compact.
You should give Google translate a go, it does a reasonable job of translating from French to English - it is literal but once you get into the translated text and study it for a while you get to know that there is no river but that they really mean current. I speak a second language and at times when watching a foreign language film with subtitles you can see the translator has put what is meant not what is said. |
6th Jul 2020, 10:08 am | #3 |
Triode
Join Date: Aug 2008
Location: Marlborough, Wiltshire, UK.
Posts: 44
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Re: French Valve Tester project (Lampemètre FC2010)
If you are thinking of using thumbwheel switches, I can recommend KSA-2. I bought them from China some years ago at very reasonable cost for use in my version of 'Sussex'.
I specifically wanted a physically larger switch for the largest separation between pads (I wanted to cold switch at least 250V and 1A) - the little thumbwheel switches are not up to the job of switching Va/Vg2. These KSA-2's have a good action and I have had zero problems over many years of operation. One tip - when delivered, dismantle them and check the PCB for any whiskers between pads - the etching is not up to Western standards. Cheers, Marty |
6th Jul 2020, 10:49 am | #4 | |
Diode
Join Date: Nov 2016
Location: Seattle, Washington State, USA.
Posts: 7
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Re: French Valve Tester project (Lampemètre FC2010)
Quote:
Since it's nearly a 10 year old project now, I thought there might have been a chance someone here on the forum might have built one in the past and had some files already available in English. There's no rush. I'd like to build the Sussex first and then perhaps I'll take on this project. I had been looking at those switches in the past. So, it's nice to have a recommendation for them - thanks! Originally was thinking to use them in a resistor substitution box that I've yet to build. Those switches are often listed on ebay and AliExpress for decent prices. |
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6th Jul 2020, 4:28 pm | #5 |
Nonode
Join Date: Mar 2008
Location: Aberdeen, UK.
Posts: 2,857
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Re: French Valve Tester project (Lampemètre FC2010)
Its great to hear that more & more Forum folk are taking up homebrew valve tester projects. From my own experience its a slow, but invigorating process. Involving quite a measure of "Suck it & see" design considerations.
Right enough, the 9 pin/9 way switching design involves a lot of thought & temp. circuitry pencil drawings. I've a thread running in "Test Eq." about a Roberts Valve Tester", and another associated thread in "Components" about Wafer Switches - particularly RS Components' MAKA SWITCH rotary switch construction kit. I've a spare AVO VCM Thumbwheel Switch assembly, but its too an expensive spare for my MK3 if anything ever went wrong. I had considered stripping out a lovely old Muirhead Decade Resistance Box, of Lab quality, for the 10 way switches, but thought that I'd probably be blackballed from the Forum if I did. So I'm plumbing for the MAKA switches, 9 newly bought 2P on/off/on Toggle switches, and some 2nd hand Yaxely type paxolin rotary switches recovered from the Roberts'. In fact, just this morning, I've decided to use a spare AVO8, fitted into the cabinet, to measure most of the valve's electrode's voltages & currents. Instead of fannying about with several different meters & heaps of shunts & multipliers. I reckon myself & many other forum valve testing enthusiasts can build a self-designed versatile DC valve tester for under 200 quid tops. Some folk might want an easy mA/V display Dial/Pot relating to an AVO-like bridge network, but me thinks that a simpler method of introducing delta Vg to the grid is achievable, whilst observing Ia. Regards, David |
6th Jul 2020, 8:59 pm | #6 |
Nonode
Join Date: Mar 2008
Location: Aberdeen, UK.
Posts: 2,857
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Re: French Valve Tester project (Lampemètre FC2010)
Homebrew Tester-wise, as well as deciding on multi-contact switching, a good source of voltage & current measurement is needed. Yep, one could fit several independent meters, and then have to fanny about calculating the required shunts, multipliers,& circuitry. On the other hand, why not use a well trusted VVM or Analogue MM, such as a Marconi TF1041C or a good old AVO8 or 9 ?
My DC Tester( housed in an empty Marconi TF995A/2 Cabinet, with the top 1/3 of an AVO VCM MK1/2 mounted on top), uses a TF1041C, and I've just decided to use an AVO9 Mk2 for the Roberts Hybrid. Both are cheap, reliable, and a common sale item at BVWS or VMARS Swapmeets/Sales/Auctions. The AVO's excellent safety cut-out & Rev.MC facility is a bonus. I've always been all for re-using or adapting tried & trusted old items of test gear - morphed & given a new lease of life. Regards, David |
9th Jul 2020, 10:00 pm | #7 | ||
Nonode
Join Date: Jun 2016
Location: Bognor Regis, West Sussex, UK.
Posts: 2,300
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Re: French Valve Tester project (Lampemètre FC2010)
Quote:
http://tsfsepelliere44.e-monsite.com...-fc2010-1.html then OCRing it using an on-line OCR service then using google translate. I attach the first 2 pages. I will try and clean up the rest and post it. I do not speak French by the way. Peter |
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10th Jul 2020, 9:44 am | #8 |
Nonode
Join Date: Jun 2016
Location: Bognor Regis, West Sussex, UK.
Posts: 2,300
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Re: French Valve Tester project (Lampemètre FC2010)
Pages 1 to 5 attached.
I will tidy the rest and post it. The process is quite involved, the article at the web link I posted above is a series of pictures. I used cntl A to select the whole thing, then copy and pasted into word having first set the margins to 2mm. Next I removed stray text and resized the pictures to fill the pages. Then printed to pdf using Foxit.Then used an on-line OCR service having first told it to recognise french. The fun part then starts, I am translating the text using Google translate in blocks and reformatting as I go to retain the look of the original. The pictures (figures) all have to be snipped from the original and pasted in as the OCR program has tried to translate them. I am not trying to translate the figures, as they say in the best text books, I leave that as an exercise for the reader. Peter |
10th Jul 2020, 12:50 pm | #9 |
Nonode
Join Date: Jun 2016
Location: Bognor Regis, West Sussex, UK.
Posts: 2,300
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Re: French Valve Tester project (Lampemètre FC2010)
This is the complete part 1.
I will post Part 2 when complete. Peter |
10th Jul 2020, 7:30 pm | #10 |
Nonode
Join Date: Jun 2016
Location: Bognor Regis, West Sussex, UK.
Posts: 2,300
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Re: French Valve Tester project (Lampemètre FC2010)
Part 2 plus appendix and errata
Peter |
11th Jul 2020, 2:59 am | #11 |
Heptode
Join Date: May 2005
Location: Adelaide, South Australia
Posts: 541
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Re: French Valve Tester project (Lampemètre FC2010)
Just looked at the full online article - I wondered how the original designer handled the matrix switch - quite clever.
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13th Jul 2020, 9:07 am | #12 | |
Diode
Join Date: Nov 2016
Location: Seattle, Washington State, USA.
Posts: 7
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Re: French Valve Tester project (Lampemètre FC2010)
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