Batboard

This has been discussed here before, and I know because I did some searching but nothing had any good solid solutions to this.

Someone pointed out that with a reed switch or relay, something you could build a repeater from two spectras, even though the COR isn't available from the 15 pin connector.

What I want to do is take the receive audio from an 800Mhz talkgroup and patch it over to UHF... either way, I've got two spectras and figure this could work out somehow.

-Josh

Josh, you mean 'cross band repeater, don't you?

It has been done, but to make it sound good it required some mods on the Command board. You also need a slight delay both ways on the PTT as the Spectras are too fast keying up, and both Spectras can get locken into TX. It is not just some wires!

Will wrote:Josh, you mean 'cross band repeater, don't you?

It has been done, but to make it sound good it required some mods on the Command board. You also need a slight delay both ways on the PTT as the Spectras are too fast keying up, and both Spectras can get locken into TX. It is not just some wires!

Indeed, but all I need is a one-way link, from 800 to UHF.

-Josh

"Indeed, but all I need is a one-way link, from 800 to UHF. "

-Josh

OK, that makes it somewhat easier.

The problem with Spectras is that they're wired from the factory for "rs-232" operation through the accessory connector...such as when they act as a radio modem in a SystemWatch application. Don't ask me why when 99.999% of them will NEVER be used in this fashion. So, jumpers on the command board have to be moved to enable things like 'TX audio in' & PTT. Once that's accomplished, you're still right about no COR being present at the connector. What I've used is the DC biasing voltage on either external speaker lead. I run it through a 4.7K resistor to the base of an NPN switching transistor. The collector connects to ground, and the emitter connects to the PTT line of the TX radio. When the receiving Spectra gets signal, the DC bias trips the transistor which in turn grounds the PTT lead. I've used the same circuit to activate external lights upon receive as well. Works great, as the circuit acts as a buffer between the external speaker lead & the PTT lead too.

Todd

I got a PM from another board member, RESCUE161, who offered assistance on the matter, and with his help I've successfuly built the link I needed to make a simple repeater that will suit my needs.

So, I guess this thread has served it's purpose. Thanks!

-Josh

Glad it worked out for you.

RESCUE161 wrote:Glad it worked out for you.

What's the method?

It's a repeater module that Riciticitembo gave me the plans for. No mods to the radios are necessary. I've had mine up and running in secure mode for over a year now with no trouble. I can send you my layout and pictures if you want. I drew the board layout in Paintbrush which makes it a snap to build. You just plug in the parts exactly where they are on the picture and solder them in place. It uses a reed relay, a couple of LEDs, a capacitor and few resistors. I only mapped out the "one-way" repeater, but the plans are for both cross band and regular.

I would like to see that info! I'm starting to play around with the Spectra's and would be interested in that.

http://batboard.batlabs.com/viewtopic.p ... 306#245306

Here is the link to the repeater module that I built. I posted it in the Hardware Forum, because I thought it fit very well there.

I've had this module on two Securenet Spectras for over a year and have had NO problems. The only issue was if the power went out, I had to manually turn them back on. I've since fixed that by modifying the control heads. I bypassed the power switch, so the radios are always on and can not be turned off via the switch. I had to do it this way because the pin on the 15-pin connector that needs 12V to turn the radio on (Ignition Sense) was being used by another pin.

Admins/Mods please feel free to move combine as you see fit.

Just to let you all know (whether you care or not is anyone's guess) but I set the repeater up the way I wanted to and tested it all out with 100% success. For $25 of Radio Shack parts, it can't be beat... it's just a shame (M) never made a real spectra repeater apart from te PAC-RT thing.

-Josh

So,

This is the reason I can't get the PTT to work with my Spectra on the accessory connector while trying to interface to a repeater controller. What jumpers on the command board have to be swapped; and where do they go? Damn, I've just about pulled what hair I have left out. I'm glad I found this post!

Victor, KB5AKO
[email protected]

wavetar wrote:The problem with Spectras is that they're wired from the factory for "rs-232" operation through the accessory connector...such as when they act as a radio modem in a SystemWatch application. Don't ask me why when 99.999% of them will NEVER be used in this fashion. So, jumpers on the command board have to be moved to enable things like 'TX audio in' & PTT........
Todd

Oh,

I have a 40 watt dashmount in UHF.


Victor

Hey,

I've done a little research and it looks like I need to abort trying to interface the Spectra and get an M-120, GM-300, or something similar.

Victor, KB5AKO

I build a cable for 2 hi power specters with RESCUE161’s drawing, the relay works great, it’s transmitting anything it comes up in the Rx radio. But the audio is very lo on the TX side of the repeater on a listening portable, like when you talk in to the mic from 5 ft. away.

You need to turn up the volume on the receiving radio

Yep, you have to adjust the volume for the best performance. I set mine in the RSS so it's always right where it needs to be.

I also modified the control heads so they will auto-power on if the power ever fails and comes back on.

Thanks for the info; I adjusted the volume and its better now. Is there a way to get the mdc1200 ID on a portable listening to the repeater? Like on the kenwood tm-700 it has a billed in repeater option and it gives me the unit ID.

If you would like to have COR on the Spectra, here it is for the following:

Spectra High Power; Audio PA IC (TDA 7256) Pin 10 (PA Enable)

Spectra Mid/Low Power w/HLN6094B; P505 Pin 19

Spectra Mid/Low Power; Audio PA IC (TDA 7256) Pin 10 (PA Enable)

In ALL cases COR is HIGH.

For Mid/Low power Spectras, the jumper can be brought out on Pin 12 (VIP 1).

High Power can be jumpered to J0006 Pin 16 (VIP 1).


Have fun with this info

Dan

Do you happen to know where the reclocked audio coming out of a hybrid carrier could be tapped?

Scott,

Still looking throught the manual and data sheets I have.

Dan

The manuals that I have do not have the diagrams/schematics, so I'm at a loss.

Any help would be a great help.

Thank you!

gentlemen

it looks like we are tring to do the same thing. I have a 900 spectra that has 2 25 pin d connectors on the front see the following post

http://batboard.batlabs.com/viewtopic.php?t=67607

what I need Is to get all the information for the pin out of the interconnect jumpers.

will it work on a astro spectra since the pin out are the same

911-EMT wrote:will it work on a astro spectra since the pin out are the same

Yes and no

The pinout is not the same out-of-the-box. Modifications (jumpers) have to be added and removed from the command board to change it from RS-242 serial operation to things like flat RX audio, mic, and PTT.

Out-of-the-box, using the repeater module mentioned in this thread, the radio will work fine for RX as-is, but not TX without the mods.

-Josh

Another option is If you have a W7 Spectra Consolette with either the local or tone remote control board, there is a very simple method of connecting two units via the DB-25 connector on the rear of the housing. This is detailed in Appendix 1 of the service manual, something like page 84 (from memory). It is a simple 6-wire interface to each radio's DB-25 accessory connector.