Help with finishing Rock-Mite 40...

[2E0MLL]

Hi Folks,

I've built a Rock-Mite 40 as part of getting my next license, but I've got stuck with two small points at the end...

The first thing I'm not so sure about is the GND from the DC power socket that comes with the control pack. In the instruction guide it says take the right hand leg of the power socket to GND, although it doens't suggest a suitable point to take this to. I *think* that the case or the braided part of the antenna is a suitable GND, so thats what I've done for now, taken it to the same solder point as the braided antenna - can someone confirm this is correct?

The second thing I wasn't sure about is the power cable - I have a twin cable with black and black/white stripe parts to it, and a power fitting to solder it to, I wasn't sure which way around to wire the cable - I think I need to do it this way:

Centre - Black/White Stripe - which would connect to Red on my PSU
Outer - Black - which would connect to Black on my PSU

Again can someone confirm this is right?

I'm looking forward to taking it to a club to test it!

Thanks!

[G3TXQ]

The first thing I'm not so sure about is the GND from the DC power socket that comes with the control pack. In the instruction guide it says take the right hand leg of the power socket to GND, although it doens't suggest a suitable point to take this to. I *think* that the case or the braided part of the antenna is a suitable GND, so thats what I've done for now, taken it to the same solder point as the braided antenna - can someone confirm this is correct?

That sounds right. I believe the square corner mounting pad on the pcb immediately adjacent to the coax braid connection is also GND, so alternatively you could put a solder tag under a mounting screw in that position and solder to it.

The second thing I wasn't sure about is the power cable - I have a twin cable with black and black/white stripe parts to it, and a power fitting to solder it to, I wasn't sure which way around to wire the cable - I think I need to do it this way:

Centre - Black/White Stripe - which would connect to Red on my PSU
Outer - Black - which would connect to Black on my PSU

That's the usual convention - the conductor with the white trace is usually use for the positive connection and the solid black one as ground. To be safe, I'd check with a multimeter that the lead you are going to connect to PSU positive IS connected to the positive terminal on the PCB before you apply power for the first time.

Good luck!
Steve G3TXQ

[2E0MLL]

Thanks Steve!

In getting the information for posting this, I've gone over the instructions again and realised I've not grounded the crystal cases either, so probably would have had a bit of noise from the kit - so I've got another job to do too

Thanks for replying! Three more jobs and I'm done!