SVA DB25 connector

[va3wxm]

I've found the pinouts for the accessory connector on the back of the SVA. A couple of questions:

1) Where's the ground?

2) Is the audio output line-level?

I'm thinking of building a crossband repeater using the SVA as the receiver portion. I can use pin 5 as the COR/COS line and grab audio from pins 20 and 21 (presuming the output is line-level).

Anything else I should consider?

[kb0nly]

If you want a good ground use the power cable ground as your reference. Pin 5 will work as your COR/COS, it goes high on receive.

I had to use an amplified speaker from another convertacom on it, i tried a regular speaker but the audio level was too low, so it is a line level output that is not amplified. However, remember that the audio output level does change with the front panel volume control so make sure nobody changes it if your going to use that.

Also make sure that you don't ground either audio line, i believe that the SVA speaker output is floating like most other Motorola gear.

[va3wxm]

Also make sure that you don't ground either audio line, i believe that the SVA speaker output is floating like most other Motorola gear.

Just like Kenwood! I'll be sure to hook up the audio side of things through an isolation transformer.

As an alternative to the SVA chassis can I use V- (pin 2 or 3) as the ground?

[kb0nly]

I was never able to find a manual or schematics for the SVA but i would assume the V- is ground. Try checking continuity from V- to the power ground and see what you get.

[va3wxm]

Just checked and V- is indeed chassis ground.

Good to know.

The audio output is quite low but can be adjusted with the volume button on the front. I can hear it but it's definitely not loud enough for a mobile speaker application.

[kb0nly]

When connected to the amplified speaker though it will pop the windows out, well, at least rattle them!

[va3wxm]

I know. I sold an SVA with the amplified speaker a couple of years ago and I remember it being nice and loud.