Saber SVA no transmit

N7LXI · Post by **N7LXI** » Sun Jun 18, 2006 9:09 pm

I'm looking for some troubleshooting help.

I just mounted an SVA in my Jeep for my Saber III, and while the display mic will show the radio info and it will receive fine, it will not key up.

I've tried a different mic and cleaned the contacts on the radio... no joy.

Any thoughts?

AEC · Post by **AEC** » Sun Jun 18, 2006 9:51 pm

The control board of the SVA is under the framework and radio opening, the accessory port connection swings up and makes contact with the radio's accy. port, if there is no transmit, the SVA control board is probably defective, it's not a simple fix as it's all controlled via a single micro and ancillary chips.

The SVA uses the opt-sel pins as well as the B+ pins to select either internal or external mic, spkr as well as the display mic's signals which take over for the internal display of the radio(which still functions aslo).

You also have volume controls and PL disable(monitor) controls on the front panel which also take over the ch. selector and volume control, with keypad entry of DTMF and zones, Etc....

A lot is handled by the SVA once the radio is inserted...

N7LXI · Post by **N7LXI** » Sun Jun 18, 2006 10:02 pm

Let me clarify; the volume control and monitor button function, but no "charge" light comes on whe the radio is inserted. The display mic reads all of the radio data as I change channels. I'm wondering if this could be as simple as the radio not seating correctly or the assembly that swings up in the sva having a defective pin?

If it's not a simple fix, it's not a huge deal... a Saber SVA is currently going for less that 20 bucks on flea-bay.

jmr061 · Post by **jmr061** » Sun Jun 18, 2006 10:41 pm

Is it wired properly, two wires should be powered if I remember right for the radio to charge, don't know if that controls the tx function.

Jason

AEC · Post by **AEC** » Mon Jun 19, 2006 3:49 am

That explanation clarifies things a bit....

There are two wires that are for B+ and IGNITION(orange I believe), and the IGN. lead is the switched power lead, then the B+ ties to a hot, fused connection.

The ground is self explanatory.

The other lead is for the DIMMER option to control lighting brightness with the vehicle's dimmer control.

If the multiple pins inside the SVA are oxide coated or bent, you will probably not charge the battery, but if the charging regulator is D.O.A, it's not a big deal either as the radio should still function but will not charge.

If you leave the battery in the charger/SVA and use the radio, you will eventually fry the battery as they are not designed to be used in this manner on a constant basis.

N7LXI · Post by **N7LXI** » Mon Jun 19, 2006 1:58 pm

OK... I guess I'm not being 100% clear. I am aware of how to wire the SVA into the vehicle, it powers up no problem.

Here's the list of what's what...

1) The convertacom powers up.

2) When a Saber III is inserted, this is what works:

a) The external speaker works
b) The Volume control works
c) The PL defeat (monitor) works
d) SVA display mic shows channel data.

3) Here is what DOES NOT work with a radio inserted:

a) No tranmit when the external mic is keyed.
b) No charge indicator lights.

4) Things I've done so far:

a) Tried a different microphone
b) Cleaned the contacts on the Saber III.
c) Tried a different Saber.

And yes, the Saber is working fine when NOT in the SVA.

The question is, do I need to junk this SVA or is it a simple issue of a pin not making a connection?

Tom in D.C. · Post by **Tom in D.C.** » Mon Jun 19, 2006 3:27 pm

The charging indicators not working could mean the contacts
inside the low end of the SVA are not making contact.

Also, see if the antenna on the radio is radiating. If it is then
the internal antenna switchover sensing circuit of the radio
has failed. I've had one Saber over the years that did exactly
that.

FireCpt809 · Post by **FireCpt809** » Mon Jun 19, 2006 6:40 pm

What battery are you using? I have had the same issue with using a short NimH battery

N7LXI · Post by **N7LXI** » Mon Jun 19, 2006 8:13 pm

I tried it with all the different batteries I have. Long, short, NiCad, NimH...

No luck.

I think this thing is going in the "junque" pile.

AEC · Post by **AEC** » Mon Jun 19, 2006 11:04 pm

With the radio NOT going into transmit, the OPT-SEL lines from the SVA are not controlling the radio's INT/EXT antenna control, and also not 'telling' the radio to switch from receive to transmit when the PTT is depressed......bad SVA logic board.

corruptRSS · Post by **corruptRSS** » Sun Jun 25, 2006 4:09 am

i was playing w/ a new NTN5487B a few weeks back. as indicated above

There are two wires that are for B+ and IGNITION(orange I believe), and the IGN. lead is the switched power lead, then the B+ ties to a hot, fused connection

the ignition sense was required to be 'high' for the unit to xmit. when unpowered, the unit failed xmit.

N7LXI · Post by **N7LXI** » Wed Sep 27, 2006 3:32 pm

corruptRSS wrote:i was playing w/ a new NTN5487B a few weeks back. as indicated above

There are two wires that are for B+ and IGNITION(orange I believe), and the IGN. lead is the switched power lead, then the B+ ties to a hot, fused connection

the ignition sense was required to be 'high' for the unit to xmit. when unpowered, the unit failed xmit.

Sorry to revive an old topic, but this WAS the issue...

Both the IGN (yellow) and B+ (red) need to be energized to xmit.

Saber SVA no transmit

Saber SVA no transmit

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