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Old 28th Aug 2012, 3:45 pm   #41
Refugee
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Default Re: Date Coding for Hunts / Erie capacitors

I have found some more to add to the list:-

TD space W
TA space W
SH space W
Plus two non Hunts caps dated Nov 1961 and Dec 1961.
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Old 29th Aug 2012, 3:05 pm   #42
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Default Re: Date Coding for Hunts / Erie capacitors

Three more very tight matches, weeks 48, 49 & 52 year *1, with a space in the less common position but one that makes sense for WWY codes. For completeness, we still need to find codes around 1966 with both W WY and Y WW sequences, and their equivalents without the space, to find out what was going on with the space and the sequence getting out of step.

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Old 29th Aug 2012, 3:29 pm   #43
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Default Re: Date Coding for Hunts / Erie capacitors

They are unlike any of the ones we change and are rated at 2KV with resin seals.
They will be military types as they are in a radiation counter.
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Old 9th Dec 2014, 6:10 pm   #44
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Default Re: Date Coding for Hunts / Erie capacitors

It's an old thread but there's some new info. Someone seems to have either started out from the same point with a bit more info, or built on the work in this thread (there's no backstory or attribution) and come up with an alternative and compelling scheme for the later codes here: Cap date decoder at Vintage Amps Forum

He had access to a number of units built in this period all of which gave codes with 0 or 1 in the second position, decoding reliably in the form Year-Month-Month instead of our proposed Year-Week-Week. All of the codes we had considered in this thread to be YWW also work as YMM, generating a more probable distribution, with the exception or Richard's N WI 7 13 which is invalid both as WWY (week 71) and as YMM (month 13). Given the data set offered in the linked thread, I'm inclined to think of this as an error or exception for the moment.

The post also contains data for 1970s Daly caps, and extension of the TCC scheme to RS-rebadged versions. As yet, we have no scheme for Dubilier...
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Old 9th Dec 2014, 7:33 pm   #45
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Default Re: Date Coding for Hunts / Erie capacitors

Why bother dating them when you're automatically going to be consigning them to the great celestial trashcan?
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Old 9th Dec 2014, 8:28 pm   #46
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Default Re: Date Coding for Hunts / Erie capacitors

Because if they are original, they date the equipment they are in and sometimes that is important. Granted, some collectors and users of vintage electronics aren't greatly interested in the provenance of their collection. It's nice to own and use, and that is that. But if one is archeologically minded, the item as it stands today can be a window on the past, through which you can learn about the people and circumstances that brought it into being. In this case, any and every clue is potentially informative, particularly for rare and sparsely documented items and firms.

I mentioned electric organs earlier in the thread. Since the Whitsunday code was cracked, I have used the dates gleaned to trace the arrival and departure of members of manufacturers' staff, the success or failure of certain models, the sequence of development of other components. They have confirmed that one instrument I have was an experimental forerunner of a successful model, that another was built to special order after the model was discontinued, etc.

The historical value of the dates depends on the item under consideration but in any case, if you are going to desolder and discard information, it's good to know what it is you are discarding.
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Old 10th Dec 2014, 6:59 am   #47
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Default Re: Date Coding for Hunts / Erie capacitors

I'm totally with you Lucien. I always try and note all codes on all parts in old valve amps, whether it helps at the time in dating the amp or not, and yes have sometimes gone back and looked through that data for particular issues.
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Old 10th Dec 2014, 3:43 pm   #48
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Default Re: Date Coding for Hunts / Erie capacitors

If the item is something of historic importance rather than just an old thing to be made to work then the last thing you want to see is it peppered with nasty little yellow tubes (that haven't been concealed in a nice old date coded Hunts greasy case).

Peter

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Old 10th Dec 2014, 9:15 pm   #49
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Default Re: Date Coding for Hunts / Erie capacitors

But the capacitors weren't all greasy and discoloured when the set left the factory! They would have been shiny and new themselves once.

Call me a heretic if you like, but I really don't mind the look of modern components. Maybe it's just what I've grown up with .....
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Old 10th Dec 2014, 9:47 pm   #50
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Default Re: Date Coding for Hunts / Erie capacitors

Quote:
Originally Posted by G6Tanuki View Post
Why bother dating them when you're automatically going to be consigning them to the great celestial trashcan?
What is a code for, other than to be broken by those excluded from the message?

I don't object to modern passives either, especially in a regular-use set when it gives the reassurance that the good, scarce bits, i.e. the valves and wound components, won't get wrecked for the sake of small outlay.

Of course, there's the conservation point of view to be taken into account for something that's scarce or historically significant.
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Old 11th Dec 2014, 1:27 pm   #51
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Default Re: Date Coding for Hunts / Erie capacitors

I wasn't trying to imply that the original capacitors bearing these codes should be retained in working equipment, merely that the message they carry could be noted down before throwing out the caps themselves. Just as (I hope) one would not peel off and discard a tatty label from the inside of a cabinet bearing original info, without recording that somehow.
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Old 8th Jan 2015, 8:25 pm   #52
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Default Re: Date Coding for Hunts / Erie capacitors

Now what do you suppose is going on here?
I've got a Moldseal made in the BB'th week of year B.
Since when did Whitsunday have a B in it?

Actually this is mostly for fun because there's a simple explanation (of sorts), although that raises questions of its own.
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Old 5th Mar 2021, 3:05 am   #53
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Default Re: Date Coding for Hunts / Erie capacitors

Reopened at Julesomega's request.

There was a small delay while I recuperated from reading " The Hunts discussion needs a recap"

David
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Old 5th Mar 2021, 12:17 pm   #54
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Default Re: Date Coding for Hunts / Erie capacitors

Thanks David. I want to recapitulate on the substance of this thread, and add my latest findings.
Post #27 by GrimJosef is the definitive statement, since when others have found only a few exceptions. His solution is
WHITSUNDAY=1234567890
Trying to date a Marconi sig gen I have only the two remaining Hunts electrolytics to go by, one clearly shows YDU -> 086 which I interpret as Feb '56; the other is smeared and looks like TIG or TBS which are non-valid by this method, but TIS works and gives Nov '55

Finally, we are still waiting for the answer to Lucien's riddle
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Old 5th Mar 2021, 12:49 pm   #55
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Default Re: Date Coding for Hunts / Erie capacitors

Is your smeared code actually TDS = wk 48 1955? Not that it makes much difference relative to TIS, but I can resolve that middle character as a D quite convincingly

The capacitor with date code BBB was clearly a Hunts product but was branded RTC, i.e. a subcontract job for which the letter B might have conveyed some other information than the date. What information, and why they didn't want the date code, are other questions. See pic.

What actually deserves a re-visit is the question of later codes (with year digit first) being either Yr Wk Wk or Yr Month Month. As I noted earlier, most yield valid month numbers, which was also the conclusion of a writer on the Vintage Amps forum who listed a selection of caps from late 1960s guitar amps, all of which decoded as a valid month with reasonable distribution. While such codes also yield valid Year Wk Wk results, the distribution would be unrealistic with all manufacture appearing to occur in the first twelve weeks of the year. I linked to that thread on the Vintage Amps forum but the link is now dead and I cannot find a local copy of the content.

But there are some exceptions (such as N WI cited above) which only work in Yr Wk Wk format, since both week 71 and month 13 are invalid. Can we identify a time period for which Yr Wk Wk was used, and /or tighter boundaries on the end of Wk Wk Yr and the start of Yr Month Month?
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Old 5th Mar 2021, 1:46 pm   #56
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Default Re: Date Coding for Hunts / Erie capacitors

Yes, there's further work to do. I've not seen any pictures of Erie date codes and I'm now looking out in my scrap collections, are they the same?
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Old 5th Mar 2021, 10:26 pm   #57
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Default Re: Date Coding for Hunts / Erie capacitors

I have seen Erie-branded caps, probably made at Hunts facilities after the 1967 takeover and identical to the Hunts-branded parts in all but name, dated with the Whitsunday code. That combination did not last long, as within a year or two of the re-brand, they started using standard (ECIA style) date codes. I'd expect most examples to be 1969-1971 unless someone has more accurate info.
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Old 10th Apr 2021, 8:44 am   #58
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Default Re: Date Coding for Hunts / Erie capacitors

I have 3 amplifiers here, the manufacturing/assembly dates are fairly accurate for the complete units.

1/ has many Erie caps, all are YYS assembly tag July 70.

2/ Hunts/Erie mix but same caps, Hunts A YI & W YA, Erie A YH, assb tag April 69.

3/ just two 8uf 150v Hunts MEW, no assembly tag but guessing 1966, other RS caps are PXH,PXJ etc

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Old 10th Apr 2021, 2:37 pm   #59
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Default Re: Date Coding for Hunts / Erie capacitors

Interesting.
I'd expect the caps in the two late units to be Year Month Month style.
YYS = May 70
A YI = March 69
A YH = Feb 69
W YA = Sept 71 which postdates the assembly and I would have expected to be branded Erie. Read as Week Week Year it would be Week 10 year *9. That format was last used some 3 years before 69. and it seems unlikely to be 59, so none of these are attractive options. Oddball.
MEW isn't the date code.

It's good to keep testing the assumptions using different datasets, to find out how far to trust them.
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Old 10th Apr 2021, 4:53 pm   #60
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Excellent, yes I expect the W YA is actually a later fitment and I was wrong it is in fact an Erie.

The MEW has another code underneath UYU, which I presume is Feb 66.
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