Tone Remote Adaptor to control 16 channels, help.

[popcicle90]

Hey all,

I have a project where I need to take a Motorola tone remote adapter and attach it to a Motorola radio of some sort. I want to be able to select one of 16 channels in the radio, but in the RSS of the CM300, CDM750, 1250, 1550 all there is is Channel Select 1, Channel Select 2, Channel Select 3 and Channel Select 4 available for the accessory pins. The tone remote adapter puts out 5 bit BCD for channels 1 to 16. Anyone know of a Motorola radio with a BCD channel select accessory connector?

Thanks,

Jesse VE7LYD

[RKG]

Are you sure that the four inputs you call ChanSel 1, etc. are not in fact binary inputs?

I know we have fabbed up channel selector switches for Quantars employed as mobile repeaters using pushwheel switches from Mouser, and I believe we have also done it for CDM mobiles. (Only use 4 pins, because what we think of as Channel 1 is represented in the radio as decimal 0, and what we think of as Channel 16 is represented as decimal 15.)

[popcicle90]

Interesting... I will try this today and report back, thanks.

[HumHead]

The channel select pins on most /\/\ radios are, in fact, BCD. Most of my experience has been with CDMs, and they do it just fine.

[RKG]

The channel select pins on most /\/\ radios are, in fact, BCD. Most of my experience has been with CDMs, and they do it just fine.

I'd argue about BDC (only decimal values). With 3 pins, the point is moot, as there are only 8 combinations, but with 4 pins, BCD gives you only 10 combinations while full binary gives you 16.

(Shades of F=15; there's one in every crowd. Missed you at dinner.)

[HumHead]

RKG-

You are absolutely correct. That's what I get for dashing off a reply on a quick pass through the office. The inputs are straight binary, not BCD.

I'm sorry that I couldn't make the dinner in Boston. I'm still getting free drinks out of knowing which bodies of water make Manhattan an island...

[RKG]

Remember: if you actually find someone who knows the last body, go double-or-nothing on their ability to spell it.

[KE9GK]

Jesse,

I currently have 4 radios set up to do this on a local PD's commandplus console..and on my home one as well...each resource has 16 channels which are OP selectable from the console itself based on the function tone generated (all industry standard).

The current back room radios are GM300's connected to TNA-200's (Gai-Tronics ITA-2000). In the RSS for the GM's there are only 4 "mode steer" inputs...I am not sure which pins are associated with what mode steer option off the top of my head...but suffice to say you will be able to steer all 16 channels with only the 4 pins.

CM200, CM300, CDM750, CDM1250, GM300, and I think M1225's will all support the mode steer option.

If you need any specifics..feel free to PM me.....I have all the info you will ever need on doing this successfully!

Don

[Jim202]

Not sure what math teacher you had, but the school I went to told me that when you have 4 pins and
use BCD, I get a total of 16 combinations. Try writing it out on a piece of paper. It goes from 0000 to
FFFF. When you do that, you get a total of 16 steps. You may prove me wrong, but that is the way
I learned it and the way the the GE Delta-S and SX radios could be steered. Should work the same
on Motorola radios.

Jim

The channel select pins on most /\/\ radios are, in fact, BCD. Most of my experience has been with CDMs, and they do it just fine.

I'd argue about BDC (only decimal values). With 3 pins, the point is moot, as there are only 8 combinations, but with 4 pins, BCD gives you only 10 combinations while full binary gives you 16.

(Shades of F=15; there's one in every crowd. Missed you at dinner.)

[xmo]

You probably should have words with that math teacher!

The 'D' in BCD stands for Decimal, i.e. the digits 0 through 9 used in the Decimal numbering system

Of course, 4 binary bits do define 16 discrete states but when 16 states are defined by a Binary code then the numbering system is called Hexadecimal, sometimes just refered to as "Hex".

So actually in this case while it is correct to say that the pins on the option connectors of certain Motorola radios can be programmed for Binary channel selection format, it isn't correct to use the term "BCD"

[RKG]

I believe the following to be correct:

4-digit hex values range from 0000h to FFFFh, and there are 65,536 different values (including 0000h).

4-digit binary values range from 0000b to 1111b, and there are 16 different values (including 0000b).

A binary coded hex (BCH) switch converts hex values 0h through Fh to binary 0000b through 1111b.

A binary coded decimal (BCD) switch converts decimal or hex values from 0 through 9 to binary 0000b through 1001b, and has no settings for hex Ah through Fh.

For a spec sheet showing the truth tables for various switches, see http://www.mouser.com/Search/Refine.asp ... -301109000

My recollection of the GE radios is that, when using a 16-channel control head on a Delta, Delta-S, Delta-SX or Rangr, the control head functioned as a BCH switch. If you installed the second piggyback EEPROM in a Delta-S or -SX and used a 32 channel control head (such as the S825), you had to move a jumper in the radio deck to enable a fifth control line. (The S825 could be programmed for multiple "zones" of 16 or 32 channels per zone, but the radio deck could hold only 16 or 32 channels at one time; when you changed "zones", the control head would download the new array of channel data to the deck.)