Home » Audio » Thermionic Emissions » To anybody that's seen a MQ S-271-A...
Fine idea! [message #9878 is a reply to message #9875] Thu, 28 December 2006 17:52 Go to previous messageGo to next message
PakProtector is currently offline  PakProtector
Messages: 935
Registered: May 2009
Illuminati (2nd Degree)
Hey-Hey!!!,
Your suggestion matches what I am doing. I asked the question after discovering it was going to be quite difficult to replicate its construction details. Seemed like a reasonable question to satisfy a rather idle curiousity: did MQ ever do a real job with their clones?

My answer arrived at after discussing the topic with a few owners of the MQ product is that they did not. Seemed sort of ironic to me, as they are always selling the Ni stripe as an expensive upgrade. As long as there are few folks who bother to look at an original closely, he can leave out what ever he wishes. If I had to bet on the rest of that remarkably complex coil, I would bet against him there too.

Either way, I am not going to attempt selling these output TX's. Anybody who wants one, need only pick up the phone and speak to Heyboer. I plan to publicize the winding details for anybody to pick up and examine.
cheers,
Douglas

Re: Fine idea! [message #9879 is a reply to message #9878] Sun, 31 December 2006 00:03 Go to previous messageGo to next message
bretldwig@yahoo.com is currently offline  bretldwig@yahoo.com
Messages: 7
Registered: May 2009
Esquire
The question is, or one question is, WHICH S-271 is MQ purporting to clone, because it's my guess that over the years they varied. As time went on wire insulation and assorted materials probably changed. I would venture to state the differences had some impact on the part, but how much is an open question.

It's safe to assume they all met all advertised specs, at least when Ercel Harrison was there. But put yourself in the position of the wind line. Various people were doing these things and when they got up to speed, each had her own style so to speak. Here's the thing: the "bogey" part is one wound at a time when someone good and fast was there. If someone isn't doing them all the time proficiency suffers badly, which is why one big order is preferential to several small ones. Most shops would do a big run of the coil structures at one go if it was a catalog part and not build them out until orders came. You only had the coils in inventory then, and in states with inventory tax you arbitrarily valued them at the cost of the wire, far less than the wholesale value of the part. If the orders never came, you could easily send them to the smelter for the copper value.

In some cases those coils could have sat a long time before being lammed up and built out.

A lot of times in those days, the docs did not match the part because the engineers would draw it up, it would be proto'd and found wanting, and the engineer would come out and make verbal changes and the people would follow along. They might or might not annotate their own copies. A lot of the time really tough parts went from proto, pilot, to production with the same assemblers and ROs and there were a hard core group that were considered key operators. Remember the situation in those days with what was from the 20s on a overwhelmingly female work force. Women married and/or with kids didn't work outside the home and so they'd have considerable turnover.

Modern QC programs like ISO 9000 and TQM are designed to limit this sort of thing. But even so examples of production not remotely corresponding to drawings are legion. I think Bob Pease or Jim Williams have one story in their book where they invited a retired old gal to do one after all engineering effort had failed, and it turned out the drawing was left-for-right, which "everyone back then knew". (Pease of NatSemi and Williams of LT write books which should be read by all present IMO).

Re: Fine idea! [message #9881 is a reply to message #9879] Sun, 31 December 2006 06:07 Go to previous message
PakProtector is currently offline  PakProtector
Messages: 935
Registered: May 2009
Illuminati (2nd Degree)
Hey-Hey!!!,
Which revision he's building is anybody's guess. I read some of his stories on one of the lists ( joe perhaps ), about how Bill Pearl bought the winding machines in CA and did not buy the TX prints because the story was circuilating that all the good audio was gone. Perhaps all the current revisions really were. I have additional anectdotal evidence which also suggests that MQ's library is far from complete across the Peerless line.

I know that after I had the S265Q cloned he told me it was wrong because *HIS* drawings didn't show any mylar insulation. In between primary and secondary the insulation was mylar and paper. His 1948 drawings only showed paper...I wish I could have seen his reaction when I made a similar suggestion to your thesis: the drawings may be missing bits, either by accident or deliberate practice.

Anyway, the 271 is a wicked bitch of a coil. I doubt that the original drawings would be of much use, compared to unwinding one carefully.
cheers,
Douglas

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