C15A Wireless Signal Buzzer

[David Dunlop]

Robert. I can remember those buzzers being used in Science classes at school in the 1950's, along with the big, tall, round 1.5V Telephone Dry Cell batteries made by Union Carbide and Northern Electric. Some of the batteries had brass posts with screw fasteners and others had the Fhanstock spring clip terminals.

David

[Grant Bowker]

A modern similar product from the original supplier, Edwards Signalling.
https://www.edwards-signals.com/file...talog_Page.pdf
It is rated for 6VDC operation as well as AC. (Sorry, no 12 V seen on their website - an argument against converting trucks to 12V?) Model 725 are on ebay as low as $9US.

On edit: it looks as if at least two different buzzers were used.

[David Dunlop]

Jordan. Neither of those cables show up in the August 1942 Chevrolet CMP Master Parts List. My Wire 5 was a June 13, 1944 build with the 2K1 Box.

Be great if we had production time frames for the various CMP bodies to cross reference with.

As for the clips, for certain there was at least one holding the cable on its way up the left corner of the cab. I think it was close to the midseam where the roof attached. Will see what the photos might have to say about that, when I find them.

David

[Jordan Baker]

That would make sense they are not in the 1942 edition since the FFW didnt come out until I believe 1943.

Here are a couple of pictures of the buzzer before it was removed. The wires would be coming up from the bottom. There is one cable clip bolted to the cab wall tight against the door frame. There was also another one further along the cab wall. Its not known if these are original though.

[Jordan Baker]

Picked up my buzzers yesterday. Here is a couple small short videos of them buzzing.

https://www.youtube.com/watch?v=BqhO...ature=youtu.be

https://www.youtube.com/watch?v=XvQz...ature=youtu.be

[Phil Waterman]

Hi Jordan

Loud little video, but you can see how it would get the drivers attention even in a CMP. Modern equivalent would get a recorded message saying the driver is unavailable at this time please leave a message.

As a teenager spent several summers working in a summer camp (1960s) because of the small number of people who could drive a nonsychro manual transmission I was selected to drive the camps 1948 F5 Ford stake truck hauling 18 to 20 campers. If they wanted the driver they pounder on the cab roof. Which was similar to being inside a kettle drum.

Enjoyin your work.

Cheers Phil

[David Dunlop]

Jordan. I found some photos of the Signal Buzzer Switch and Lanyard Setup for the 2K1/2K2 Wireless Boxes. This one is the switch itself. A simple teardrop shaped cover over the spring loaded contacts that are kept in the open position by the spring until the lanyard is pulled. The Lanyard is originally a white cotton heavy sash cord which ages into a weird reddish brown over time. it is looped through the switch plunger ring and clipped back against itself with a common metal cord/cable crimp.

I can guarantee these stitches were common items in the GM 100, 150, 200 and 250 Series Transit Busses they built well into the 1980's. The buses with the green tinted windows along the upper sides and that always smelled of diesel fuel inside. If you know of a transit bus graveyard anywhere nearby, definitely worth checking out.

David

[David Dunlop]

Jordan. Here is what the lanyard rings look like and the spacing arrangement along the 2K1/2K2 Wireless Box ceiling. Only two rings are used. The second, outermost ring is equally distant from the centre one as the centre one is from the switch. The lanyard is looped back upon itself at the end ring and crimped as per at the switch.

David