ITA2000 Tone Remote Question

[Flatbush97]

All,
Due to narrow banding I recently replaced my spectra consolette with a tone remote setup using a GaiTronics ITA2000. After playing around with different dip switch settings as well as radio programming I have succeeded in getting the setup up and running. I noticed that the output volume, which is Flat Rx is significantly quieter into my C100 then it was when the console was hooked up to the spectra consolette. This is the same whether hooked up to an M1225 or a CDM1250. I have read through the manual and have adjusted the audio pot with mild improvement. Is there any other settings that I am missing? If I do not use flat audio then the volume is much louder, though the volume on the actual radio would be quite loud as well. I noticed in the manual that there is a JU30 "Converts the B+ supply to a 15 V power supply to increase audio output.". Is anyone familiar with this jumper? I am not sure I understand what it does and it does not seem to be documented in the manual. Will this help my cause?

One other question which is how to correctly put the radio into monitor mode? I have the wire out on the tone remote going into Pin 14 on the accesorry connector but dont think it is programmed correctly. Should it be set to Mic Off Hook? Active Level?

Any help is appreciated.
Thanks

[guy being a guy]

I always use "flat Rx Audio" so I think your good there.
I'm only guessing on this jumper............Maybe it increases the voltage to the audio amp section which in turn increases the overall gain and hence louder audio. If the manual states this configuration is OK then I don't think you will start a fire or anything . I would have RX audio coming through the remote and change the jumper over and see if you get an immediate increase in volume. If not, leave it where it was.
Mic off hook for monitor - YEP, thats correct. Should be grounded while "on hook" and go to "monitor" when "off hook" (not grounded).
Tone remotes and level settings are not the simplest thing so you are doing pretty good young grasshopper

[Flatbush97]

Will I need to change anything on the radio programming side? Such as enabling handset or Hang Up Box etc or will the CDM realize it is coming from the accessory connector and handle it differently?
Thanks for your response.

[RFguy]

Flat audio is typically only used for data (sends modem tones at same deviation). For voice, it should be pre-emphasis/de-emphasis for natural sounding voice.

[guy being a guy]

I believe you may be having this RX audio problem due to line loss of the wire your using . I would not run it down telco or multi strand cable more than 200ft. or so. When we run tone remotes across a city using the old Ma Bell copper telco lines the phone company puts cards on them to "condition" the line and amplify it to go the distance.
Your using low level audio so it won't go that far w/o some loss. If your just running this remote to a desk real close or something you should be using a "local" remote instead of this tone remote anyway.
Read the radio that is working right now. Look at the acc. connector configuration and write that down. Read the other radio and make the acc. connector pin out the same. Now BOTH are programmed the same and should be working. M1125 and CDM and the acc. connector for what your doing are the same.
BUT on the CDM ........When you plug in the cable to the acc. connector ............It goes in the middle - you will have 2 pins on either side that don't line up. M1225 it's not like that.
Another thing to try .........Hook up your RX audio pins on that 16 pin connector for external speaker - I think it's pins 1 and 16 . That is a like a 5 watt RX audio output. That should be enough audio to go quite far w/o loss ! This configuration WILL then leave the base with no RX audio in the internal speaker - not sure how your using it and if this is unacceptable.

[Flatbush97]

If MDC is handled through the console does it require flat audio?

[guy being a guy]

MDC is "data" ................it is the information or data burst that tells the console what unit is transmitting.
You know those darn irritating " BWWEEEKKKSSS" you hear .........Thats the MDC "data" signal which is essencially the unit ID.
The console will take that " BBWWEEEKKKSSS" noise ,and dicepher that data and display it as the transmitting unit ID.
If the incomming RX audio is low, the console may not be able to have enough input audio level to "interpert" the " BBBWWWEEKKKSS" and display a unit ID.
If the console is NOT having a problem displaying the transmitting radio ID's then the RX audio level is fine. I know you want it higher and that's cool.............MDC needs to be a certain level and it's parallel to the RX audio as a whole.If your seeing the unit ID's right now - cool.......You can keep increasing the RX audio and all is well.........

You could have taken the Spectra consolette and just decreased the TX deviation to be around 2.5 khz ( thru the service part of the RSS software) and be legally "narrowbanded" . No need to go through all this.............
I could have reduced the deviation and had my service ticket signed in less than an hour .........Oh well .........

[guy being a guy]

I bet you have at least 2 hours messing with this remote and changing the radio.
One more hour posting on this board.
Thats 3 hours of your time and it still has issues............Maybe more..................
I could just have reprogrammed the original Spectra consolette down to 2.5 Khz TX deviation and essencially "narrowbanded" for about 1 hour labor - $100 and a trip charge .
Pay the radio man and get back to what you do best please GGeezzz...............

[gtriever]

I believe you may be having this RX audio problem due to line loss of the wire your using . I would not run it down telco or multi strand cable more than 200ft. or so. When we run tone remotes across a city using the old Ma Bell copper telco lines the phone company puts cards on them to "condition" the line and amplify it to go the distance.
Your using low level audio so it won't go that far w/o some loss.

We run along copper from our dispatch center to the nearest microwave site, which is a distance of 3/4 mile (3,960 feet). On a good pair, the most loss we see is approximately 0.1 dBm.

[Flatbush97]

Actually, the consolette needed to go. The caps were changed a bunch of times and we were having issues again so definately not worth the time or effort on a 25+ year radio. I spoke to Gai Tronics yesterday and they informed me that there was an additional Pot (Pot3) on the board of the tone remote that adjusted the incoming rx volume into the adapter, not the same as the processed audio RX out pot on the pack of the adapter. I will play with it over the weekend and advise.

As far as MDC is concerned, years ago I played around with the MDTMon software (anyone remember that?) and had to take discriminator output as the filter of the radio would corrupt the signal so that the data coming out was not able to be decoded. With that in mind, my thought was that MDC is also data that is being sent as audio. I assumed that if not flat rx then part of the audio will be missing and it will not decode ID's properly which is why I wired the console the way it was done.

Thanks for your help.

[d119]

I bet you have at least 2 hours messing with this remote and changing the radio.
One more hour posting on this board.
Thats 3 hours of your time and it still has issues............Maybe more..................
I could just have reprogrammed the original Spectra consolette down to 2.5 Khz TX deviation and essencially "narrowbanded" for about 1 hour labor - $100 and a trip charge .
Pay the radio man and get back to what you do best please GGeezzz...............

This is the kind of crap that gets technicians fired and causes companies to lose service contracts. This isn't ham radio.

While your idea would work from a technical standpoint, what is the gentleman to do when someone gets parked on a narrowband channel next to what is his center frequency?

You'll wish you had those 2.5kHz IF filters...

Guy - we're mostly professionals here on this board who do things the proper way and don't circumvent the FCC or industry standards for the sake of saving a buck. Yeah, if it's the ham band, but not if it's public safety.