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-   -   Mullard Valve Tester Card Project (https://www.vintage-radio.net/forum/showthread.php?t=6112)

GMB 23rd Nov 2005 11:10 am

Mullard Valve Tester Card Project
 
I am undertaking to build as complete a catalog as possible of all the cards for the Mullard High-Speed Valve Tester. I am doing this after developing a really fast way to process the cards to obtain the map of their holes. But I don't have anything like all the cards and although I have tracked down quite a few from other people there are still many to go.

So if you have any cards for this tester and would like to help then go to this link for details...

http://home.btconnect.com/gmb/mullard.htm

Ed_Dinning 23rd Nov 2005 1:32 pm

Re: Mullard Valve Tester Card Project
 
Hi GMB, I'll have a look through the list for you; I also have details on adaptors. I've designed (but not yet built) a hole punch fot the cards.
It appears there were at least 3 versions of this tester as well as military one. All used the same cards but had internal circuitry differences. How about the CV range of cards, were they more comprehensive than the alpha/numeric ones?

Ed

Duke_Nukem 23rd Nov 2005 7:38 pm

Re: Mullard Valve Tester Card Project
 
1 Attachment(s)
I'd been putting off getting a list of my cards together, but I've finally got off my butt and done something about it ... list attached.

I have the test cards and a couple of others but can't seem to find them.

There are two versions of some of the cards (547,967b), differentiated by a letter A underneath the Mullard logo.

If you've generated a database of holes vs card, how about a utility to read the database and print out an actual size card ? I could have a bash it this if you don't fancy doing it yourself.

TTFN,
Jon

Colin 23rd Nov 2005 7:54 pm

Re: Mullard Valve Tester Card Project
 
1 Attachment(s)
Here's a list of all my cards. Simple colour code - Green I've got & Red I'm missing:)

Hope Excel 2003 format is ok. If not let me know and I'll let you have it in any format that's suitable.

rgds
Colin

GMB 23rd Nov 2005 11:57 pm

Re: Mullard Valve Tester Card Project
 
Quote:

If you've generated a database of holes vs card, how about a utility to read the database and print out an actual size card ?
Coming as soon as I have as complete a list as possible.
Quote:

There are two versions of some of the cards (547,967b), differentiated by a letter A underneath the Mullard logo.
That is something I haven't encountered so it will be interesting to see.
-------
I will contact you as soon as I have checked your lists against mine.

Duke_Nukem 24th Nov 2005 9:20 am

Re: Mullard Valve Tester Card Project
 
Quote:

Originally Posted by Duke Nukem
...and print out an actual size card ?

Quote:

Originally Posted by GMB
Coming as soon as I have as complete a list as possible.

Cool 8-)
Quote:

Originally Posted by DukeNukem
... There are two versions of some of the cards

I meant to add that they differ by just one hole, rather suggesting the first version was a bit of a monday morning accident.

TTFN,
Jon

GMB 24th Nov 2005 4:14 pm

Re: Mullard Valve Tester Card Project
 
I have updated my list based on the promised and actual contributions from a number of people. But still the list is incomplete!
So if you have a set of Mullard tester cards then please check http://home.btconnect.com/gmb/mullard.htm to see if you can help.

mikelect 24th Nov 2005 8:14 pm

Re: Mullard Valve Tester Card Project
 
I've got an incomplete set of CV cards. I will list them but don't have time at the moment. I'll be in touch when I have further news.

Mike.

Lowemission 29th Nov 2005 12:32 am

Re: Mullard Valve Tester Card Project
 
Hi George

One of the projects that I was hopefully going to start in the New Year was to find out as much info about the MHST as possible, as there seems to be many unanswered questions.

Regarding the cards, over the years I've bought several lot's of cards and still haven't a full set :'( , but how many cards were produced ?
Does anyone have any later revised editions of the Numerical List, the latest one I have is number7, which I know is incorrect as I have cards which are listed as "no issue".

How many cards were Amended?, not all cards which were amended had the letter A on them. Later on I understand that Mullard called these cards "revised" cards, I've not seen one with the letter R on or did they stop marking them?
I have many duplicates and triplicates of card numbers, many having more than one hole difference, some as many as three or four holes and some of these with no letter A.
I've tried some of these cards on my tester which have had the same card numbers but with a different configuration of holes, the cards I used all gave the same readings.
Like many of you I've heard rumors about cards which suddenly make the tester go up in smoke 8-o , I'm not planning to do too many test's like this (mainly due to time) but I do suspect that maybe some cards were amended due to the old one causing problems.
I understand that these testers are prone to the odd transformer burn out, as far as I know it's not due to any one dodgy card.

Many amended/revised cards that were sent to dealers had an accompanying letter telling them to destroy their old cards.
I also understand that this "amended card service" had to be paid for by the dealer through a yearly subscription, wonder how many dealers didn't keep their subscriptions up to date so never had a set of up to date cards.

It wasn't until a while back when I started to go through my cards did I realise just how many discrepancies there were regarding card numbers etc, also that it would be a very long slow job.

I have two different MHST manuals, one being the early E7600 type which I will scan for you in the next couple of day's.

I have the military version of the MHST, model no CTA20, sorry but I have no info at all on it, does anyone?, could send you some pics if your interested.
This tester came with two boxes of CV cards, how many CV cards were produced, who knows.

This is about as much as I know, or it should be "don't know" about the test cards.

I'm sorry but I'm not going to be able to sort my cards out until well into the New Year.
What I had planned and will do is put a wanted notice in the BVWS free ads for any info regarding the MHST, someone must have more info.

Julian

Ed_Dinning 29th Nov 2005 1:36 pm

Re: Mullard Valve Tester Card Project
 
Hi Julian, I've got the valve/card list No 8, it is up tp approx 1175 card and is hand annotated to show cards to 1196(DY82) and 1197 (EL500). I also have details of the cards to be used when the unit was fitted with a Y8A base. This will also be copied to GMB as will the data on vards got, when like you I get some time to do it.
I had heard of the rogue cards/ re-issues, but not in the detail that you have given. I will have to check my duplicates to see if there are any differences. This of couse adds a who new dimension to card classification.
The way round the problem with possible transformer burn-outs that I have adopted is to fit 200mA fuses into each of the transformer taps that feed the HT selection.
I trust one of the Forum members will host all this data when it is collated.

Ed

GMB 29th Nov 2005 1:50 pm

Re: Mullard Valve Tester Card Project
 
I will be donating the final result to the BVWS and will probably host it too.

The issue of card revisions is interesting. I haven't encountered any of these and was not initially looking too hard. My own card set is quite old and obviously forms the core of the data.

Part of the project is to analyse the meaning of the cards so I will be able to verify that nothing in the database is going to cause damage. It will be interesting to see what changed on the revised cards - so I invite anyone with these to send me images of them even though they are in the "done" list.

Anyone coming to Wootton Bassett and who has instances of the missing cards but can't scan/photo them can bring them along and I'll do them there.

Paul Stenning 29th Nov 2005 10:38 pm

Re: Mullard Valve Tester Card Project
 
Quote:

Originally Posted by GMB
I will be donating the final result to the BVWS and will probably host it too.

It can certainly be hosted on my www.vintage-radio.info site if you wish.

Lowemission 1st Dec 2005 12:28 am

Re: Mullard Valve Tester Card Project
 
Hi Ed, I'll get list No 8 off George when we exchange data.

Quote:

The way round the problem with possible transformer burn-outs that I have adopted is to fit 200mA fuses into each of the transformer taps that feed the HT selection.
Thanks again Ed, I couldn't remember what fuses you recommended.

Good news is that while sorting through a pile of service data tonight i came across another MHST service manual, this one is different from the other two that I already have, I'll pass them over to George to scan.

Julian

GMB 4th Dec 2005 11:55 pm

Re: Mullard Valve Tester Card Project
 
Many thanks to the people who have contributed so far.
After finding an unexpected 190 extra cards at Wootton Bassett to add to the database I have updated the missing card list at http://home.btconnect.com/gmb/mullard.htm.
But there is still a way to go - so if you haven't already done so, please check to see if you have some of the missing cards.

Paul Stenning 5th Dec 2005 12:05 am

Re: Mullard Valve Tester Card Project
 
I have made this thread "sticky" so it stays visible at the top if the list for now.

ajs37 5th Dec 2005 11:42 am

Re: Mullard Valve Tester Card Project
 
Quote:

Originally Posted by GMB
Many thanks to the people who have contributed so far.
After finding an unexpected 190 extra cards at Wootton Bassett to add to the database

Hi GMB - I presume you don't need anything else from the cards at Wootton Bassett yesterday? I won the machine - if you didn't have time to check everything, let me know and I'll sort it for you -
Cheers
Andy

martin4 10th Dec 2005 12:02 pm

Re: Mullard Valve Tester Card Project
 
We met at the last BVWS . Just a line on making cards I have tried many methods . Including formica, takes too long. The best and very quick is to cut your new card from the old green filing cabinet type files the ones with the metal top. You can cut out easy with scissors and make a punch from steel tube and use to punch out your holes. Easy. The card is just stiff enough to actuate the micro swith at the bottom.
Martin.

GMB 11th Dec 2005 10:53 am

Re: Mullard Valve Tester Card Project
 
Quote:

The best and very quick is to cut your new card from the old green filing cabinet type files the ones with the metal top.
I haven't seen other than cardboard ones but I presume there are some kind of plastic ones now?

It is worth noting that if you do have some good ideas for card material it must be able to happily stand 1KV across the thickness and be >100M resistance. Also, if it's a thermoplastic then you need to check whether it will get too soft from the heat inside the tester. There must be absolutely no danger of splitting or cracking as if you open up an erroneous hole in the wrong place it will cause serious damage to the tester. It is rumoured that even Mullard made errors and some genuine cards can cause damage - something that I will be checking during the compilation of the card database.

GMB 23rd Dec 2005 3:59 pm

Re: Mullard Valve Tester Card Project
 
Just a reminder to you all MHSVT owners who haven't got round to checking your cards - the latest lists are now up on http://home.btconnect.com/gmb/mullard.htm and will be updated over the Xmas holiday as and when I receive any further cards.

Merry Christmas!

GMB 4th Jan 2006 1:43 pm

Re: Mullard Valve Tester Card Project
 
To everyone interested in the history of the Mullard tester, take a look at this link: on eBay. It appears to be a hybrid of the early and later versions. Has anyone in the UK got this model? I have the early model which looks almost like this one, but the underside view shows that the EHT doubler has been added.


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