Part required: FAO Dave

[emsgeorge]

3085859M01

Its a power splitter lead for the dr3000 repeater. Will make a neat additon to my gp380 repeater set.

Can I have a price please Dave.

Is there any sort of price list for all of the parts available, or do you have to ask for every one ?

Reason I'm asking - is I'm thinking long and hard about making up a dr3000 repeater from parts - considering its only 2 dm mobile units, and a power supply, I would buy the extra bits (like case, extra heatsink etc) and see if I can build it myself.

At least it means I will shell out the cash over a longer period, and give me some fun putting it together, rather than having to shell out £1700 at once ....

[Dave]

Hi, I can't find the part number in the service manual, send Rob a PM and he will contact the supplyer for you.

Regards
Dave

[JtB]

I'm thinking long and hard about making up a dr3000 repeater from parts - considering its only 2 dm mobile units, and a power supply, I would buy the extra bits (like case, extra heatsink etc) and see if I can build it myself.

At least it means I will shell out the cash over a longer period, and give me some fun putting it together, rather than having to shell out £1700 at once ....

Be careful, while the RF bricks inside the DR 3000 repeater are obviously architected around the DM mobiles, they are NOT DM mobiles. For one thing they contain completely different firmware. You can purchase the repeater RF bricks, however I would imagine that by the time you've purchased 2 RF bricks plus all the other parts (including the connector and repeater boards) you'd have been better off purchasing a complete repeater.

[JtB]

As a follow up to my previous post, the model you describe consisting of two mobiles in a box is one that can be made to work for 'analogue', but 'digital' is a different matter. Unlike with 'analogue', the digital RF bricks do not take the signal back to baseband audio. Apart from the fact that the RF bricks in a MOTOTRBO repeater do not contain DVSI vocoders, if they were to take the signal back to baseband audio there would be a degradation in audio quality and there would also be timing issues. For a 'digital' TDMA repeater, the timing relationship between the inbound and outbound channels is critical. It is the outbound channel which defines very precisely the timing on the inbound channels to ensure that two radios transmitting TDMA bursts on the two inbound logical channels do not collide. Additionally, the outbound channel is not a duplicate copy of the inbound channel; The 'digital' RF bricks are required to correct any errors received on the inbound channel before re-transmitting the signal on the outbound channel. Also, the inbound channel as previously mentioned contains up to two incoming TDMA bursts from two different radios while the outbound channel is a continuous (FDMA) transmission containing the repeated (voice/data) payload for the two logical channels plus other signaling information such as the DMR defined CACH bits.

Another reason why two mobiles in a box wont work for 'digital' is that with DMR mobiles (such as MOTOTRBO), they only recognize incoming signals which are addressed to themselves, while the repeater has to be able to handle all signals containing a given colour code.

[JtB]

PS. Forgot to mention another fundamental difference that the DM mobiles are only able to manage a single slot at any given time while the DR bricks are required to manage both slots together.

[emsgeorge]

excellent post jtb - thanks for the info.

I assumed that the radios inside the dr3000 were simply the same as the mobile ones, with some extra heatsinks etc - and perhaps a different firmware. I didn't know that they are a completely different beast.

If they cant cope with 2 slots at the same time, I might as well get a proper one. I just dont have the cash lying around to buy one !.