Author Topic: Stromberg Carlson Military Switchboard  (Read 3241 times)

Offline rdelius

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Re: Stromberg Carlson Military Switchboard
« Reply #15 on: July 08, 2018, 12:52:49 AM »
Besides the missing jack, the cord is retractable. The operators pack  usually has the mounts for a retractable cord but no mechanism

Offline dsk

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Re: Stromberg Carlson Military Switchboard
« Reply #16 on: January 29, 2019, 01:44:28 PM »
Now I have line-packs, I just need the rest of it  ;D


dsk

Offline dsk

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Re: Stromberg Carlson Military Switchboard
« Reply #17 on: November 13, 2019, 12:19:00 PM »
Now, I know a little bit more.
The older operators packs had that retractable cords, but no jack for resting the plug. 
The handset jack is obviously switched out by some reason.

When I served we did not use the headset, but a handset: H-33 handset.

My guess is that the mod here are made for using a handset the owner had.

dsk

Offline dsk

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Re: Stromberg Carlson Military Switchboard
« Reply #18 on: January 06, 2020, 12:14:44 AM »
« Last Edit: January 06, 2020, 12:47:16 AM by dsk »

Offline Fabius

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Re: Stromberg Carlson Military Switchboard
« Reply #19 on: January 09, 2020, 08:50:56 PM »
Does yours have the tag that shows who made it? If so, who made it?
Tom Vaughn
La Porte, Indiana
ATCA Past President
ATCA #765
C*NET 1+ 821-9905

Offline dsk

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Re: Stromberg Carlson Military Switchboard
« Reply #20 on: January 10, 2020, 12:49:54 AM »
SC
« Last Edit: January 10, 2020, 01:52:32 AM by dsk »

Offline dsk

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Re: Stromberg Carlson Military Switchboard
« Reply #21 on: April 15, 2020, 08:06:39 AM »
Now I have used it for a while, and it was definitely not 100% OK, but it took time to discover some of the problems.

The first I had to do was to change the cord and plug, the cord was weared out.  (6)
The next was some problems I believed was in the switches so I measured and got some resistance.  (5) Cleaning with plain paper dipped in alcohol and keep the contacts closed.  Helped a lot!

Some later I found that the ring and sleeve had no connection.  The fault was the switch inside the generator (4)
What else have I heard others having problems? The Capacitors (2) and (3)  are also weak points, First aid suggestions: The no C301 (2) will just remove the anti sidetone, and you will probably barely notice it.  C302 (3) will make you loose the contact to the handset.  Without using a tone sender or field telephone to the contacts "EMG OPR" it will probably mean nothing to short C302 until it may be replaced of any unpolrized capacitor of 2-4 uF  rated at least 50V  If you can not get power to the transmitter it is most likely in outside the operators pack, often in the battery holder, and somtimes in the handset/headset with cords.  I can see a possible problem in the rest jack, but find that not so reasonable since those jacs are tough.
dsk
PS I really hope it works OK from now  DS
« Last Edit: April 15, 2020, 08:39:00 AM by dsk »

Offline dsk

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Re: Stromberg Carlson Military Switchboard
« Reply #22 on: April 16, 2020, 07:07:46 AM »
Since it seems to be impossible to get the original DTMF unit for the cordboard, and my trunkpack also is a DIY version, I did get inspired of the German WWII solution: http://www.classicrotaryphones.com/forum/index.php?topic=22478.msg226592#msg226592


But of course I would like to have touch tone too, so I found a scrap phone with tone/pulse selector.   I did put in a jack, and some components.   I prefere the transformer to get the systems isolated from each other, the small transformer does not like the DC components, so I did put e capacitor in series on the CO side, and added a 470 ohms resistor to keep the DC path without loosing to much of the signal. On the SB-22 side I also added a capacitor to prevent it from stealing all the ring off power.

The diagram sketch shows how I wired it.  And ofcourse you have to see how small the transformer actually is.

The best of all, it woorks great on first try.
dsk

Offline dsk

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Re: Stromberg Carlson Military Switchboard
« Reply #23 on: April 16, 2020, 07:12:32 AM »
I also have to say thank you to Brooke Clarke who has great pages with information:
https://prc68.com/I/SB22.shtml

He actually also links to this page  :)

dsk