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Now the Story Can be Told - 1949 WECo 500 Set

Started by Dan/Panther, March 20, 2010, 11:08:11 PM

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Dan/Panther

I'm at a loss after seeing Bill's EQ opened. The tube is mounted directly to the lid. I can't figure what would be the need for the screw and the nut. I would assume the entire module would be mounted to the top of the EQ. Something is going on inside that predates the tube, is my guess.
Paul, any ideas what is inside that module ?
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

Phonesrfun

Yep, it just hangs there upside down like a bat.  Probably more like a bat than a jellyfish  ;D

When I opened the can, I noticed that there is no bottom to the equalizer can.  It is completely open at the bottom to the base of the actual telephone, to which it is riveted.

-Bill G

Phonesrfun

#347
D/P

This is just conjecture, of course.  Perhaps the trial model had some other alternative purpose in mind for a possible mounting that was not actually used, and thus the nut and screw.  Or maybe they had some way of attaching the tube inside that was overly engineered at the time and later production models had an easier way of doing it.

A late-coming thought I just had.....

Maybe the varistor used the side of the can as a heat-sink which could have been later found to be un necessary.  It is not uncommon for semiconductors to use a metal enclosure for heat dissipation, especially in older semiconductors that were not as tolerant to current as the ones of today.  The varistor is a semiconductor that is essentially two opposing back-to-back diodes wired in parallel.

It is certainly curious, that's for sure.
-Bill G

Dan/Panther

Paul talked about saving tenths of cents on production costs. Imagine 1 square inch of aluminum ( The Bottom Of the EQ ) over a million phones. That would be 776 square yards of aliumium. That would save a few bucks. then figure the bottom of the Network about double the size or more.
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

Phonesrfun

I think the network does have a closed bottom, due to its being potted with some gooey substance.  I think the network can was also steel.  Probably to keep transient AC hum out from adjacent flourescent lights and transformers.  On the other hand,  the 302 101A induction coil was routinely completely un covered, but they did make a metal shield for the 101A that was occasionally used, but I don't know under what circumstances.
-Bill G

Jim Stettler

I lean towards it being part of the mounting assembly and/or heat sink.  I wouldn't be surpised if the main purpose of the nut is to hold the cover in place.

In the bureaucratic world  it is not unusual to overdesign. The extras can be cut later for budget or attaboy reasons.  Many times "fluff" is encouraged, so it can be eliminated later.

In the case of BTL, the intial design/production cost, would be  tagged as R&D, and would get written off, rates could get based on development cost. Later if you could cut cost, the savings go into the profit column.

Design first, simplify later.
Just a thought,
Jim
You live, You learn,
You die, you forget it all.

Dan/Panther

Earl "Madman" Muntz, would go into his engineering Department, and clip components out of the prototype televisions. He would keep doing that until the engineers could no longer make the set work.
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

paul-f

Quote from: Dan/Panther on March 31, 2010, 10:08:25 PM
I'm at a loss after seeing Bill's EQ opened. The tube is mounted directly to the lid. I can't figure what would be the need for the screw and the nut. I would assume the entire module would be mounted to the top of the EQ. Something is going on inside that predates the tube, is my guess.
Paul, any ideas what is inside that module ?
D/P

I don't know what's in there either.

Perhaps Bill's photo has given you the courage to try and pop the top off to take a look inside -- while hoping feverishly that the screw isn't connected mechanically to anything mounted to the terminal strip, or that they left enough play to allow the equalizer to be assembled after the nut was tightened.

While we're on the subject of cost cutting, saving the cost of the screw, nut and labor to drill the hole and assemble the parts would really add up in mass production quantities.  Not to mention what might be inside that was also eliminated.
Visit: paul-f.com         WE  500  Design_Line

.

Phonesrfun

By the way, here is a page out of one of the documents we have been looking at from last week.  It is a grainy shot of the equalizer, and it is undoubtedly the production version.

PDF file is attached at the bottom of this post (1 page)

-Bill G

JorgeAmely

#354
Excellent job Bill. I am sure this is the first modern picture of the equalizer tube ever taken.

Remember the 426A tube we discussed in the past and the method used to fasten it to the base? Brinybay took a few pictures of the tube in his AE80. In that phone and like in later 501 phones, the socket is held to the base with a screw. It is possible that inside D/P's phone there is a similar socket held with a screw and nut like in the 501 phone.

Since his is a field trial phone, it is possible that the engineers chose to mount the equalizer in a socket until they refined the circuit and found the most optimal equalizer model.

Once production began, they eliminated the socket ($$$ in the long run) and mounted the final equalizer tube directly to the terminals of the box lid.
Jorge

Phonesrfun

Jorge:

That is possible too.

My early 500 is also equipped with a cold cathode tube and is attached to the base of the phone with a single screw.
-Bill G

Jim Stettler

Jorge,
That is a very good point, w/ a socket you could try out variations of tube design. once the tube was finalized there was no longer a need for the socket. The exsisting  tube may have a model # or date on it.


Jim
You live, You learn,
You die, you forget it all.

Dan/Panther

Boy Jim you really like to dangle that carrot don't you. Got me thinking the only part in the entire phone that may be dated or traceable is in that EQ.
Well, All I can  say is, We'll never know then will we  ;D
Or maybe I'll open it up and look, and be the only one in the world that knows what's inside. :o :o Then again, maybe I already have looked 8)

D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

Jim Stettler

Quote from: Dan/Panther on March 31, 2010, 11:47:13 PM
Boy Jim you really like to dangle that carrot don't you. Got me thinking the only part in the entire phone that may be dated or traceable is in that EQ.
Well, All I can  say is, We'll never know then will we  ;D
Or maybe I'll open it up and look, and be the only one in the world that knows what's inside. :o :o Then again, maybe I already have looked 8)

D/P
Frightening, isn't it.

But doesn't the public have a "right" to know?

(a quote I heard somewher).
Jim
You live, You learn,
You die, you forget it all.

JorgeAmely

Jorge