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Old 15th Feb 2018, 9:48 am   #33
dagskarlsen
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Join Date: Jan 2008
Location: Hakadal, Norway
Posts: 642
Default Re: Kellogg wall phones - need help

I am pretty good on making konfusions, but here we have to clarify some points.

1) I would rather say this is a Leich than a Kellogg

2) The pretty well designed triad circuit is a CB circuit, this is a LB circuit. LB ciruits did usually not use a booster circuit, except for where it was a modified CB circuit, and the transmitter was powered by a local battery, and a choke. (Typical US Field telephone TA 312 TP )

3) The extra set of contacts on the inductor was for use when silent ringing was used.

4) Local battery, anti sidetone circuits was usually made as a bridge, pretty equal to the triad mentioned over, but with no capacitors as anything else the a DC or ring frequency blocking/breaking. much more to read here: http://www.samhallas.co.uk/repositor...i-sidetone.pdf

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