Kenwood and Narrowband

[LubeckTech]

Is anyone having problems with some Kenwoods not opening squelch with analog and digital PL tones in narrowband mode??

Motorola and Vertex radios work well on the same systems.

We are having problems with TK-790 and TK-2312 radios.

 

[ramal121]

Yes, at least with the 790. In the service mode, the squelch open/tight settings need to be aligned BY THE BOOK in narrow mode. For some reason, when these are outta whack, prevents QT/DQT decode. I have pumped 0dB into a radio with the proper code and no receive until I re-aligned (funny though, in monitor the squelch seems to work normal).

 

[car5le]

Yeah, we're running into that same problem with our 790's. I can get into the service mode, but I want to chat with someone before I go adjusting anything. And I'm looking at nearly 1000 of these to tune up.

Anyone here willing to give me some guidance?

 

[cabletech]

Do you have the service manual for this radio? Most Kenwood radio's have a VERY strict alignment procedure and if you do not know what that it, you will always have trouble.

The alignment on 98% of the kenwoods deal with BOTH aligning narrow band AND wide band.

I have about 60 Kenwoods +90 series (both handheld and mobile) and I have then all working just fine and I go by the manual.


If you do not have the manual, then contact kenwood for one, and you MUST use a good service monitor.

 

[ramal121]

An excerpt from Kenwood LSB-0247. Note the last line, you must have a calibrated signal level into the receiver so the correct RSSI level is memorized. Do NOT go into the service mode and twiddle the adjustments without a RF generator!



A summary of the squelch adjustment is:
1) Measure the 12dB SINAD point of the receiver. (example: 0.21uV [-120.5dBm]).
2) Increase the signal generator level 7dB (example: 0.47uV [-113.5dBm]).
Adjust "squelch tight" to the threshold where squelch is open at this signal level.
3) Decrease the signal generator level by 3dB from the level which produces 12dB SINAD from step #1 (example: 0.14uV [-123.5dBm]).
Adjust "squelch open" to the threshold where squelch is opened at this signal level.*

* For proper squelch operation, a signal must be present while making this adjustment.
LSB-0247 2/2

 

[cabletech]

This procedure is not only for Kenwood, but can be used for EVERY manufacture. If you align radios like this you will never have a problem.

Only GOOD radio tech's (on a scale of 1-10) have less then a 1 on radio squelch problems.

 

[car5le]

Thank you all! I do have the service manual an will give it a shot.