Batboard

I have used, for years, a Comtest Systems (Industrial Electronics) CLT-500 tone remote tester. Some of you old-timers may be familiar with it, while you new guys will go 'Huh?' For those of you who are familiar, do you know of any vendor who's currently marketing something similar?

not sure who still makes a standalone box for just tone remote testing.
I used to cheat and use a small tone remote for the basic two channel tests and use a R1150A or the service monitor for the more complex bases.
Lots of Motorola R11XX series tone signalling generators on Ebay and the mid to later versions had tone remote built in.
The later Motorola and IFR service monitors had that built in as well .

Analog remotes in general have really dropped in usage given that most public safety users needed a more complex remote solution for the 800 trunk systems

What are you trying to accomplish? Level setting? I set levels out of a tone remote desk set using a TIMS; set the LLGT for -30 dBm, or maybe -25 continuous, and a TIMS will give you both level & the frequency. No, it's not fast enough to catch the 40 mS function tone, but I'd pull out the storage scope for that, as well as looking at the timing parameters. And on the CPI TR-10 series, one of dip-switches on the bottom locks up the function tone, and sets it at 0 dBm.

The wild idea that comes up in my head would be to get a CPI multi-tone termination panel (TTP10 or TTP216) and do some redneck engineering with it so that you could have some sort or level detector circuit, and of course the LED's indicate that you have proper decode of a particular tone. Even just a TTP2 to find out if you've got 1950 or 1850 Hz, if that's as far as you need go.

I could be wrong, but with the advent of synthesized tone generation (the CPI series remotes use some sort of PIC chip to do most of the work) tone frequency is pretty tightly controlled, so I wouldn't worry about them being too far off. After that, the important stuff is level, and timing. I've just looked at the theory of ops of the CPI TTP216 adapter, a lot of timing & tone detection is done in the PIC.

???

kb4mdz, I think you misunderstood. I don't need to test the Tone Remote, the CLT-500 takes the place of a tone remote for testing wireline functions to the base/control station. You can generate Guard Tone, Function Tone, Xmit Burst, Function Burst, etc; the output is variable via a pot on the front of the unit, it also has external tone input, adjustable function tone length, and a local speaker for monitor. Here's one example of where it came in handy:

We had an Astro Digital consolette which was linked back to a Gold Elite console via analog microwave; kept having problems with the thing falsing and self-keying, staying on the air until it timed out. By using the variable output of the CLT-500, we found that the TRC sensitivity (as factory set) would hold the radio keyed all the way down to a -51dBm level (which was down in the noise floor of the microwave). I won't go into all the details of why it was falsing, but adjusting the sensitivity to a more reasonable -35dBm dropout solved our problem.

Yes, I could get a multi-channel Tone Remote and modify it if the need arose (right now all of the CLT-500s we have are still working); I'm just curious to see if anybody still makes something similar to this animal.

Yup, I misunderstood, you're right.

I can see where that would be a bear to troubleshoot, and what you have would be a godsend. I hpope what you have continues to give you years of service; they sound like they are worth their weight in gold. If I ever run across a similar problem I 'll have to do just that and open up a remote and bring the level control out where I can reach it easily. No, I don' t know if anybody makes an off thelf unit.

Never heard of the CLT500. It probably would have helped once or twice. I've always used a tone remote or a service monitor to gen keying tones for test.

Microwave transport / T1 mux are lossless systems, and tend to be very quiet. Not all of them have a method to inject "comfort noise" to mimic long lines which had the benefit of masking inaudible reflections and echoes of pure tones. Inserting attenuation on the input or the output, or both, helped knock down those reflections especially if you have long in house lines to the terminating device where ringing could start. Sometimes it helped to increase the line load with a parallel resistor to snub low level stuff.

A pic would be awesome. I find no trace of this thing on google etc. I have never seen such an animal, but it would be awewsome to have a device like this.

Here you go, Rob.

Nope. Nobody makes something like that anymore.

escomm wrote:http://comtekk.us/tone-generator.htm

Cool stuff!

Does anyone have a scan of the manual for the CLT500 or the CLT1000?

Most Motorola Service Monitors have generators built in for those functions also.

MANY SERVICE MONITORS HAVE THIS BUILT IN. i KNOW THE MOTOROLA R2600 AND variants d0 this. I seem to recall my old HP also did it.

With micro processor monitors it is easy to include. It is just an include item to the software engineer. I have not looked at my IFR units but it would not surprise me to see it.

An external box is best but in reality you are looking at your service monitor anyway so you may as well use the included function.

the HP's never did as far as I know .

The COM-120 did have this ...may have been part of an optional signaling package though. May have been in the 1600's as well ...not sure without pulling the manual. As mentioned the later Motorola Service Monitors had this built in ( r20XXD, R22XX,R24XX and r26XX ). May have been in the 200XA/B/C's as well.

Always used a tone remote for field testing though.

On the bench the R115X tone signaling generator was used to troubleshoot and repairs

Damn that test box is really cool, too bad they aren't around anymore. I'd have all kinds of use for that at work!