This is the Continental Equipment Section of
The Broadcast Archive

Maintained by:
Barry Mishkind - The Eclectic Engineer
Last updated 2/6/10

The Continental 315 & 316 Series

The 315 (5 kW) and the 316 (10 kW) transmitters were essentially the same, 
aside from the Power Amplifier - the 315 had one less PA tubes than the 316.

This transmitter used a Doherty modulation system. 

315/316 - 1941

KRLA used their 10 kW unit for about 18 years before it became the driver for the linear amp which brought them to 50 kW - and formed the third 317 model..
Dave Hultsman recalls: The original 316 10 kW transmitter (a three cabinet transmitter) was the driver for the 317 50 kW at driver at KRLA and WDIA and CKWX.

This was essentially part of the Western Electric line after CE bought the Western Electric AM product line. I understood that CE also sold some of the 316's as 10 kW's opnly in the US, Canaga and worldwide. 

Robert Meuser notes: "A number went to the military. We had them in Germany (glass doors) along with 314's (1KW)..."


315/316B - 19xx

The 316B had three 4CX5000A tetrodes in parallel, screen modulated by 4 each 4-65A tubes in the screen circuit. The 315B used only two tubes.


Robert Meuser: "A very deadly TX" 

315/316C - 19xx

Dave Hultsman recalls: The 316C had two 4CX10,000 tubes in parallel operated in linear mode, screen modulated by three 4CX250B tubes. (The 315 only used one PA tube.)

I remember there was one at WCFL and one at WLAC backing up their 317C's. I know of several of the 315C's, Boston MA, WRR, Dallas, WMAK, Nashville.

Robert Meuser: "I believe they called the modulation scheme 'regulinear.'"

315/316F - 1971

A 316F         

Dave Hultsman recalls: "Finally, something that Sainton was working on in 1968 when I was looking at transmitters for KLIF's new 12 tower array. They had a working prototype 10 kW two-tube solid state transmitter. 

"They finally got it out about 1971 as the 315F and 316F, using two 4CX10000's in the 5 kW and two 4CX15000's in the 10 kW. The tubes operated in a Doherty amplifier making it more efficient than running in linear fashion as the two previous models. The also set it up so you essentially peaked the grids and dipped the plates which was the way most class C plate modulated rigs tuned.

"These two transmitters were the FIRST two-tube 5 and 10 kW AM transmitters and predated the MW-5 from Gates and by several more years the MW-10 from Harris."

Robert Meuser: "The 316F was the goal post Harris used for development of the DX line -  especially the 50 kHz audio response [and]  excellent square wave performance that came with that. 

"The problem with the 316F was the trade off between positive modulation and distortion performance. When you got near 125% positive the peak tube started to shift from AB1 to AB2 causing a large drop in drive impedance and thus requiring much more power from the exciter. You can see the positive peak on a scope flatten out on the exciter output. 

" I have seen a few 316Fs modified to have a 250 W SS TX as a replacement for the original 50W exciter to solve this problem. I know of one that took the sample TX output of a Motorola AM stereo exciter, applied a 500 W SS Linear and then drove the 4CX15000s. Fantastic stereo AND great positives. I also know of one and only one unit (un modified) that had nearly 50 db stereo separation, less than 1% distortion and could just barely make it past 125% mod, all at the same time."


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315 - 5 kW Series
First unit to KHYM (1060), Gilmer, TX 

315B - 5 kW
First unit to KPAM (1410), Portland, OR

315C - 5 kW
First unit to WMAK (1300), Nashville, TN

315F - 5 kW
First unit to KUOA (1290), Siloam Springs, AR

315R-1 - 5 kW
First unit to KGER (1390), Long Beach, CA

315T - 5 kW - Solid State (1995)
First unit to XECD, Puebla, Mexico

316 - 10 kW Series
First unit to CHLN (550 kHz) Trois-Rivieres, Canada
Pictured: KRLA, Pasadena ... The difference between the 315 and the 316 was the output tube and voltage.

316B - 10 kW 
First unit to CKRC (630 kHz), Winnepeg, Canada

316C - 10 kW 
First unit to XERC (790 kHz), D.F., Mexico

316F - 10 kW 
First unit to CJOB (680 kHz), Winnepeg, Canada

316F-1 - 10 kW 
First unit to WHOO (990 kHz), Orlando, FL

316T - 10 kW - Solid state. Original model name: XL310
First unit to KUTR (860), Salt Lake City, UT