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WB5AGF

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Topic Created Posts Views Last Activity
a substitute for Ebonite (for Marconi PS213A) ? Jun 29th 2016, 02:44 3 1,113 on 1/7/16
Archived 'QST' Quality & Readability Sep 18th 2014, 03:43 2 1,118 on 19/9/14

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Cheap paddle cover K6ZIZ on 4/7/16

Last winter I was looking through a small box of 'fleamarket-keys' (I kind of remember how I came to have them but am not completely sure) and I came across one that I think is of eastern European origin - it looks to be sort-of-a-copy of the German Baumuster Key. I could tell that the key originally had a snap-on cover but that was missing.

On a pantry shelf I had a container of Borden's 'Craftbond' glue (it looks about like Elmer's Glue-All).

I took scissors and cut up some thin cardboard until, by folding, I had a small open top container ... turn it over and there's a cover. Then I took the glue and smeared it fairly liberally on the paper (this glue is similar to the stuff they had you use in kindergarten so it's slow to set and it washes off easily). Then I covered the box with some green felt (another item I have as a result of collecting old keys) and waited for the glue to set.

When the glue had cured I had a surprisingly presentable top cover for the CW key (other than I think that using black felt would have looked better than the dark green felt that I had on-half).

I have not done so but I've been wondering if smearing more of the glue on the outside of the felt (in effect using the felt/box as a casting form for the glue), and then letting it dry, then sanding the glue so it's smooth - might this not give an almost 'proper' looking cover (perhaps with a spray of black paint) ?

- Paul, WB5AGF
Antique keyers -- value? W0SJF on 1/7/16
You ask "If I buy a nice, old keyer and refinish it does it reduce it's value?" .... my opinion (and you know what they say about opinions .... :) .... 'yes' to a 'collector' and 'no' to a 'user'.

If you have a really rare (and perhaps technologically important) key then I'd suggest that you refrain from doing any significant work on the key - consider selling it to a 'collector' and find yourself a more 'day-to-day' key that you won't feel guilty about if you fix-it-up like you want.

With something like the former Soviet straight keys that are on eBay all-the-time for twenty dollars (before shipping) it doesn't bother me at all to 'snip' the hard (read non-flexible) wires that were used to complete the circuit around the pivots and replace them with a flexible piece of braid (doing this dramatically improves the way these keys feel).

But (my 8th grade English teacher would wince) for the 19th century 'Steiner' straight key that I (somehow) bought off eBay for a decent price ... with it anything I'd do would have to be able to be undone (for instance to get the shorting bar to work correctly I put a small piece of wax paper between the bar and the body of the key to reduce friction so moving the shorting bar repeatedly doesn't cause the securing screw to loosen).

- Paul, WB5AGF
a substitute for Ebonite (for Marconi PS213A) ? WB5AGF on 1/7/16
Hi Zach;

I've got an inquiry off to one of the sellers on Amazon, asking if they know the hardness of the rubber blocks they are selling.

In a prior discussion (with a very decent fellow in the customer support group of a rubber company in Minnesota) it was brought to my attention that products make of rubber (including modified rubbers like Ebonite) have their physical characteristics described (one of the tests) by their resiliency to being deformed when a predetermined force is applied over a small surface area (it's called the ' Shore Durometer ' test). My research indicates that Ebonite would feel, if we were to have a piece to press on, quite hard (about like a hard plastic).

In this ' quest ' of mine (imagine me as a knight on a might steed ..... OK maybe you don't want to imagine that ...) to build a ' proper ' PS213A I've been very aware that a significant goal is that the key will 'feel' to the user just like a real PS213A and since I don't have one as a sample I have to hope that by staying with the right materials, and the same dimensions, that whatever I build will closely match the performance of the real thing.

- Paul, WB5AGF
a substitute for Ebonite (for Marconi PS213A) ? WB5AGF on 29/6/16
I've given myself a task .... that being to make a copy of the
Marconi PS213A Morse Key.

I'm aware that GØNVT makes a key based on the PS213A
(but there are differences) and G3YUH had made copies in
the past (but he isn't making them anymore). My intent is to
try-and-make as near an identical a key as I can.

(My 'yardstick-of-success' would be that you could site down
at a real PS213A or my key and not detect any difference
in the way the two keys feel in use.)

One of the problem I'm facing is that the original Marconi key
used 'Ebonite' (vulcanized rubber) for the base - finding a
source is proving daunting. I've even downloaded Charles Goodyear's 1844 Patent but when I read it I lose-heart ....

At one time bowling balls were made of what was called
Ebonite but it isn't clear to me if it is really the same thing
or if a 'trade name' was being used for something different
than Goodyear's 19th century creation.

Thoughts ? Suggestions ? (I'd really rather not try and saw
a bowling ball in half.)

- Paul, WB5AGF
Archived 'QST' Quality & Readability WB5AGF on 18/9/14
I am slowly going through the older issues of 'QST' (2011 and earlier) to learn what hams were doing in prior decades (my real time knowledge begins in the 1960s with spotty exposure to QST issues from the 1950s).

The technique I have stumbled onto as the most workable is to download an issue's Table Of Contents, open that up in my computer's PDF viewer, and then work my way through the articles that (from their titles) appear to be interesting. (Sometimes this doesn't work very well - hams can be terrible at choosing titles that give an inkling of what the associated article is about! This is especially maddening when you can remember reading something when you were a kid and are trying to find the article but the title was chosen whimsically with no regard for being descriptive.)

I must say that often the quality of the archived magazines run from 'passable' to 'poor'. Very often finely detailed visual content (most often graphs) is unusable and it is not uncommon to find that the last pages of an article were not scanned and converted into the PDF document. I 'click' on the 'submit-for-correction' link but very seldom have I gotten e-mails back telling me that the articles have been corrected. (I suspect that QST articles from way-back-when are not very high on the priority list of things-to-fix.)

- Paul, WB5AGF

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