BC-474 Telegraph Key Info
A lot of collectors have a BC-474 and the set is fairly common. However the actual Speed-X key telegraph key that was used with the set is scarce. It is theorized that the key was purchased off the shelf and not subdued or painted in any way due to the Emergency. After the War Emergency E.F. Johnson purchaed Speed-X and they continued to manufacture the Speed-X line of keys.
However to the best of my knowledge E.F. Johnson never manufactured the key with provisions for the thumbscrew which was designed for the BC-474 front lid. Details and drawings below.
At
present Wm M. Nye Company is making Speed-X keys using the same molds
etc. that the original "Speed-X" keys were made from. However
the crome plated keys are no longer advertised. Mr. Nye purchased Speed-X
in 1972.
An additonal note: /Email confirmation with Mr.
Nye confirms that the key is not longer available in chrome.
Speed-X logo
K4CHE photo
The Famous Speed-X logo is shown above. In this case it was stamped on the key lever near the pivot points. Note the small arrow pointing to the X. Later there may have been cheap copies made overseas but the logo did not have the arrow pointing to the X.
This photo was lifted from a video on YouTube. The chrome Speed-X key mounted on a black wooden base is clearly visible with the BC-474 in the foreground. I lost the link.
SCR-288
system diagram taken from the manual. The Speed-X key is shown mounted
to the lid. I think the BC-474 is a great military radio as its easy to
maintain and I've even modified mine to cover 80 and 40 meters.
CLICK to enlarge Radio New Photo November 1942
Another photo from "Radio News" 1942. The Speed-X key is clearly visible.
Here is a link to the "Radio News" issue, the photo is in the color section
starting at page 50.
http://www.americanradiohistory.com/Archive-Radio-News
Click to enlarge K4CHE photo
My key shown above on a 'working" display at Ft. Miles in 2015. This key was given to me at a Gilbert MRCA meet by Jeff KG2BZ. It belonged to his Father WA2FSX. The small OD box contains a switching power supply for the BC-474.
Emidio WA2FSX
My key before I mounted it properly on a black wood base. Not sure about the significance of the red paint.
N3FRQ/AB5S
photo
The
bottom of the wooden base has a recess hole for the threaded fixture which
is mounted on the lid of the radio.
Right side of the open lid showing the key mount fixture. Which I will describe as a captive or insert nut which is press fitted to the lid.
Captive nut with 8-32 thread.
Exterior view of the hold down fixture.
The thumbscrew is retained underneath the base and can not be removed from the key. GI proof.
A retaining washer prevents loss of the thumbscew.
Photo by Dave Stinson AB5S
A very nice key owned by AB5S. Note the "inspection stamp"
AB5S Photo
Inspection stamp, with measurements - - further measurement on a diagram below.
N3FRQ/AB5S
photo
Most of the chrome Speed-X keys that may have been used on the BC-474 are missing the thumbscrew but if you see hole on the left side of the key near the rear it is probably an ex BC-474 key.
These
thumbscrews were manufacted by master craftsman Mike KC4TOS - link below.
Be sure and scroll down the page.
K4CHE photo
My key with a fabricated wooden base and inspection stamp. There are numerous rubber stamp dealers on ePay - just send them art work and they will make a stamp.
Photo
by AB5S
Click
to enlarge
Dave
Stinson's key base with measurements.
A copy of a sketch drawn by Paul N6FEG.
CLICK here to download PDF file of the above sketch by Paul N6FEG
Photo by N3FRQ/AB5S
I am not sure of the wood but it does not look like it was laminated but it appears to be just plain pine painted black.