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

radioben 16th Mar 2013 2:42 pm

Re: Mullard Valve Tester Card Project
 
Looking forward to the finished project. In the meantime, I was wondering whether there were any jobs that I or other forum members could help with? Also, whether it would be possible to share the card scans in their raw form so far? :-)

McMurdo 11th Apr 2013 10:09 pm

Re: Mullard Valve Tester Card Project
 
5 Attachment(s)
a few scans of HSVT literature in my manual here.

jamesvalves 9th Feb 2014 2:06 pm

Re: Mullard Valve Tester Card Project
 
Hi,
I have just aquired a tray of CV MHSVT Cards, GMB are you after copies of these cards? Also looking on your website it looks like you don't have a copy of 227 And I have found 1 in my Collection . Also how do I go about getting all the pixtures/ Hole details of cards I don't have?

Regards
James

GMB 10th Feb 2014 10:52 am

Re: Mullard Valve Tester Card Project
 
The CV cards are just differently presented versions of the commercial cards. It was just that they were stored indexed by valve instead of by card number, thus making it a little faster to use (and no lookup list to loose). So just look to see if you have any that are in my list of missing cards.

Card 227 is interesting. I have encountered a number of these, but so far the thing that I don't know is what valve it tests - so do you have that information?

jamesvalves 10th Feb 2014 3:46 pm

Re: Mullard Valve Tester Card Project
 
Ok, I will have a look through all my Mullard Books and lists. Can you supply the pictures of the cards that you have on your list?

jamesvalves 17th Feb 2014 11:04 am

Re: Mullard Valve Tester Card Project
 
The card 227 mystery has been solved, I have found it in one of my Mullard Test Card Index 5th Edition to be used for the Cossor 215P valve

In the front of this book it states that the following numbers have not and will not be allocated to standard cards
95, 98, 120, 128, 141, 165, 171, 172, 173, 175, 176, 198, 204, 216, 220, 226, 229, 231, 239, 247, 254, 260, 266, 275, 276, 281, 287, 289, 303, 305, 322, 324, 326, 330, 441, 448, 459, 481, 482, 483, 500, 503, 537, 538, 539, 540, 544, 545, 551, 556, 559, 564, 585, 588

So if any of the missing or no issue cards aren't on this list they may be in this booklet...

jamesvalves 17th Feb 2014 4:36 pm

Re: Mullard Valve Tester Card Project
 
It also gets a mention in Test Card Chart 4th Edition, 3rd reprint as Cossor 215P Card 227

GMB 17th Feb 2014 4:53 pm

Re: Mullard Valve Tester Card Project
 
That list of unissued cards is interesting in being a little short of previous lists.

Needless to say it is now known that the unissued cards do exist, well some of them at least. They tend to show up in the military cards, so if anyone has one of these then please check.

I would be interested to see a valve list that says what is tested by some of the previously thought to be unissued cards.

ukcol 2nd May 2014 8:13 pm

Re: Mullard Valve Tester Card Project
 
4 Attachment(s)
On the same theme as post 31, I have just been testing a batch of valves and came to test an ECC84. The card index gives 713ABC for this valve. See pictures below.

Each card is labelled TRIODE and using all three doesn't give any nasty results, suggesting the valve was good (including the phantom extra triode). ;D

In the fourth picture I have overlaid cards B and C which reveals that they are nearly the same. The left-hand hole highlighted in yellow is present only on card B and the right-hand one only on card C.

Did Mullard correct this problem in a later revision? Can I solve this problem by discarding card C (or card B) or is there a completely different revised set of 713 cards?

ukcol 2nd May 2014 9:09 pm

Re: Mullard Valve Tester Card Project
 
As a post script to my post above it occurred to me that I might be able to answer my own question by comparing the cards for the ECC84 with those for the PCC84. After all these valve types, with the exception of the heater rating, are identical.

So, I looked up the cards for the PCC84, OH DEAR, there are 3 of those as well - namely 655ABC. There are differences between the 655 cards and the 713 cards of course because of the differences between the heaters but my comments on cards 713B and 713C apply equally to cards 655B and 655C.


There are also 3 cards for the UCC84
:shrug:

Ed_Dinning 3rd May 2014 7:28 pm

Re: Mullard Valve Tester Card Project
 
Hi Gents, has anyone ever listed what the various switches (and associated holes) do, in terms of voltages applied, test limits set etc?
It would seem that this should answer most of the questions ref "3 cards for a twin triode".

Ed

ukcol 3rd May 2014 9:26 pm

Re: Mullard Valve Tester Card Project
 
Hi Ed

Agreed, knowing what each switch contact in the matrix does is the key to solving this sort of problem.

Further investigation of the 713 card problem reveals that card C tests the same triode as card B (no surprise there) but, perhaps surprisingly, the voltages on the valve electrodes remain exactly the same whether using card B or C. There is also no change in the heater voltage.

It looks like the difference is going to be in the test limits as the emission test using card C shows a slightly higher reading than for card B.

If nobody has already done this I shall have to go through the manual and list what each contact does.

ukcol 6th May 2014 3:41 pm

Re: Mullard Valve Tester Card Project
 
3 Attachment(s)
(See post 89 to 92 above).

I believe I have solved the "problem" of cards 713ABC.

As mentioned cards 713B and 713C are almost identical except for 2 contacts. On card B the tester connects to the lower triode of the ECC84 via contact D4 of the gate switch to pin 7 of the valve. Card C uses contact D5 of the gate switch to connect to pin 8 of the valve.

The valve has pins 7 & 8 connected together internally (see picture) and are for the cathode of the lower triode. This valve is designed to be used as a cascode VHF amplifier in TV tuners, hence the term "lower".

So it follows that card B tests the lower triode using the pin 7 cathode connection and card C tests the same triode using the pin 8 cathode connection.

In my picture of the ECC84 the cathode connection comes out at pin 7 and the added link goes to pin 8. I have concluded, therefore, that this is not a mistake by Mullard and that the third card is to test the integrity of the pin 7 to pin 8 link.

A similar argument can be made for cards 655ABC (for the PCC84) and cards 911ABC (for the UCC84).

I have also included pictures of 2 circuits using a PCC84; In the Bush one pins 7 and 8 are not joined externally to the valve, in the Philips circuit they are. If the weld failed on the link inside the valve the Bush may display a fault symptom whereas the Philips may not.

Edit. I mentioned in an earlier post that the tester displayed a slightly higher emission an card C than on card D; whether or not this observation was real or imagined, it was nothing to do with the change of cards.

Ed_Dinning 6th May 2014 6:38 pm

Re: Mullard Valve Tester Card Project
 
A good bit of detective work Colin!

Ed

ukcol 6th May 2014 11:21 pm

Re: Mullard Valve Tester Card Project
 
Thanks for that Ed. I was convinced that I was going to find it was a mistake by Mullard as was the case with the 967ABC cards (see post 31), but Mullard are not at fault on this occasion.

I would be interested to know what all 130 contacts in the gate switch do but unless someone has already worked this out it will have to wait until I have the time to do the work myself.

mole42uk 7th May 2014 7:35 am

Re: Mullard Valve Tester Card Project
 
In the AVO tester instructions for use it is recommended that double triodes are tested with the anodes linked together. I haven't looked at my ECC8x cards for the Mullard, but could it be that the 'C' card had this function?

The circuit diagrams for the Mullard testers are widely available, AFAIR one of the drawings in my filing cabinet has the contact grid detailed - it has to be fairly trivial to work it out.....I'll happily send a scan of the circuit to anyone who wants to do that.

Richard

ukcol 7th May 2014 8:22 am

Re: Mullard Valve Tester Card Project
 
Quote:

Originally Posted by mole42uk (Post 679602)
In the AVO tester instructions for use it is recommended that double triodes are tested with the anodes linked together. I haven't looked at my ECC8x cards for the Mullard, but could it be that the 'C' card had this function?

From my investigations (above) the answer must be no. What does linking the anodes test for?

Quote:

Originally Posted by mole42uk (Post 679602)
The circuit diagrams for the Mullard testers are widely available, AFAIR one of the drawings in my filing cabinet has the contact grid detailed - it has to be fairly trivial to work it out.....I'll happily send a scan of the circuit to anyone who wants to do that.

The scans for the Mullard HSVT models are available on GMB's site. These include the layout of the gate switch and schematics of the tester circuits. Tracing the functions of the switches will be straightforward enough but very time consuming since there are 130 of them.

Alan Brown 29th Oct 2014 7:22 pm

Re: Mullard Valve Tester Card Project
 
Hi, all. The following may be superseded by now but in the March 2012 card list cards 1070 and 1082 are described as not issued. My edition 4 list shows 1070ABC issued for valve ABC1 and 1082 issued for 10LD13. Regards, Al.

robot797 3rd May 2015 3:26 pm

Re: Mullard Valve Tester Card Project
 
i may be late or somthing

but i may have found a oddball

my tester came with a lot of cards missing (if somone has spares for me i keep myself reconmended)

but mine also had a 9th adapter socket

it is an offical socket and i have not traced it

ukcol 3rd May 2015 6:05 pm

Re: Mullard Valve Tester Card Project
 
The manual for the last version of the Mullard HSVT lists 9 valve adaptors and a number of adaptors for CRTs. But there are more. I have eleven.

Adaptors 1,2,3,4,5,6,7,8,9,10A and 13.

1 to 9 are as listed in the E7600 MK4 manual, adaptor 10A is for the PL500 valve and 13 for the PFL200.


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