• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
  • Click here to find out how to win free radios from Retevis!

CBC INTERNATIONAL Speech Processor or ???

unit_399

EL CAPO
Jun 17, 2008
2,314
3,741
273
ALEJANDRIA, COLOMBIA SA
I have a couple of the PC boards for Lou Franklin's speech Processor (clipper). I have assembled one, and thinking about installing it in my Superstar 360FM. Has anyone had any experience with this board ?? It seems to be a copy (almost) of the clipper used in the 858SSb chassis.

Some History:
Back in the late 80's, we were living in SoCal, and I was running a Galaxy 2100, TX600 amp, and a Francis Amazer antenna in my mobile. I had a 150 # Caterpillar tractor battery and a 200A alternator that powered the CB only. I had taken the speech clipper board out of a Superscope CB640 and grafted it into the 2100. I didn't care about harmonics and such back then, so the 2100s limiters were cut, and I even removed the TVI trap.
I had run this setup without the speech clipper for a while, but after I installed it everyone said my audio was up. It was one loud-talking SOB.

I love my 139XLR. It has served me well for almost 50 years. One of the best features of the 139 is the built-in speech clipper. It is loud and clear, even with a stock mike. But I want to go higher in the 11 meter band, and the 139 just doesn't have the bandwidth. I could realign it, but I would lose a lot of the regular 40. So, I'm putting together a 360FM to use when I want to go to 27.555.

I don't want to clip the limiter, but I want my audio to be loud so it will punch thru the QRM. I want to add a speech clipper to do this.

My question is:
Which board should I use ?? The CB640 board or the CBC International ?? The 640 board is harder to install as it uses an additional regulated power supply board to power the clipper. It is a PITA to install. The CBC board is stand alone and is an easy install. BUT . . . I want the best result. So, which way should I go ?? Neither of these boards have a filter to remove clipping harmonics so I will have to add one.

Anybody had experience with the CBC board ?? I'd love your opinions.

J.J. 399

BTW . . . sorry this was so long-winded.
 
Last edited:

Yes, had the cbc in several radios back then 29 gtl ,JC penny 6247 one in a Pluto.
My experience was it worked well, it does just what is supposed to do and just like other speech processors you can overdrive it / clip too hard with it.
On a AM radio you could ride it kinda hard and no one noticed to much but in a ssb radio you need to dial it back some as clipping hard starts to sound bad quickly.
I got a CPI talk power tp-1a speech processor that plugged inline with the Mic and stopped using the internal ones because I could adjust it for what mode I was on.
I would just build it and put it in, easy to take out of you don't like it.

73
Jeff
 
Yes, had the cbc in several radios back then 29 gtl ,JC penny 6247 one in a Pluto.
My experience was it worked well, it does just what is supposed to do and just like other speech processors you can overdrive it / clip too hard with it.
On a AM radio you could ride it kinda hard and no one noticed to much but in a ssb radio you need to dial it back some as clipping hard starts to sound bad quickly.
I got a CPI talk power tp-1a speech processor that plugged inline with the Mic and stopped using the internal ones because I could adjust it for what mode I was on.
I would just build it and put it in, easy to take out of you don't like it.

73
Jeff
That would be neat if it could be put in a box so it could be ran inline like the one you have.
 
That would be neat if it could be put in a box so it could be ran inline like the one you have.
Had.
When I was young I traded away lots of things that I had that are now inobtainum.
But you can build Lou's board into a box.
American Electronics used to also make a outboard processor that shows up on fleabay from time to time.

73
Jeff
Screenshot_20231118-091614~2.pngScreenshot_20231118-091731~2.png
 
I am not as talented or experinced as you with electronics in fact I am idiot by comparison. I can plug and play and populate a board and do very mild trouble shooting mostly because I have not made time to advance my understanding and skill.

So with that said I head the CBC internation is diffacult for most to install and adjust properly but have no actualy installed one or used one. I have used SP-1a's which are imposible to find new mostly a used item now and hard to find they were easy to install and adjust.

I would recomend an external unit that can be used on any rig. 2 I have used that I like and recomend. 1) MFJ LSP 520BX II Logarithmic Speech Processor 2) Ten-Tec 715

Both of the above are RF Speech Processors. The MFJ is the bargin basement GEM if you can find a good used one deal of a life time while the Ten Tec 715 is about the best external Speech Processor you can buy and add to any unit period in my opinion.

I spend 65% to 85% of my time on SSB rag chewing and the rest on AM since these units are external you can always sound the best for given mode. I under stand you can make an internaly mounted processor adjustable well.

The MFJ LSP 520BX II Logarithmic Speech Processor is easily usable in mobile application either with resistors or regulator transistor to drop 12V down to 9V nominal. All steel case makes it easy to punch or drill new holes. The Ten Tec uses 12V but it is larger and combination of plastic and steel so not as mobile friendly. It is also close to lifetime unit. Going from memory it has one disc capacitor and all the rest are stryroflex. It has a crystal and one IC if I am remembering corrrectly.

Just some things to consider should one of either become available.
 
I built the Lou Franklin speech processor\clipper about 6 years ago or better. I didn't have the pre-made board, only a schematic and some proto board. I was able to build a working version but couldn't get it to stop feedback squeeling using it for CB. It works great away from a radio, say running a guitar through it (for fun effect) or microphone. I know Lou mentions maybe needing some chokes on the audio lines to correct the feedback, but I didn't have any. I'll see if I can find it.
 
I recall Lou's instructions or advertisement saying it would not work on the President, Cobra, or Uniden 8719 radios, due to the bad squeal. I can't remember if he listed others that it would not work in, but it was supposed to work on some radios.
The squeal was RF feedback getting into the unit, putting it in a metal enclosure was not an option, apparently the mic cord was picking up the RF.
 
  • Like
Reactions: tecnicoloco
I have a few external speech processors. A Daiwa, which is good and the best of the best. The ETO Alpha Vomax. There is nothing better in my opinion.
 
I’m just going to leave these 2 pages from Lou’s assembly/installation instructions. It may help “tamp down” the squeal in some applications. I have one of these boards and have built it but never installed it in any radio. May try it soon since this thread reminded me that I even had the board.

IMG_5688.jpegIMG_5687.jpeg

73
David
 
  • Like
Reactions: Shadetree Mechanic

dxChat
Help Users
  • No one is chatting at the moment.