NavWorx pin 35 question

I have the ADS600B and I'm following the "ADS600-B to AFS Interconnect Diagram" from Navworx to connect to my AFS 4500, GTX-330 and GNS-530W.

On the diagram, it calls out a connection from pin #35 (suppression output) on the ADS600B to "Transponder suppression input" on the transponder. It does not provide a pin assignment for the transponder. In looking at the GTX-330 install manual, I see there is a "External Suppression I/O" on pin #31. Is this the correct pin to connect too and what is the purpose?

I do know about the need to connect pin #33 on the ADS600B to a RS-232 output on the transponder for remote control, but don't recall anybody discussing the use/need for pin 35.

Yes pin 31 is correct on the 330, this is a mutual supression pulse that inhibits transmission of the "other" unit so they do not transmit at the same time and cause interference with each other.

Walt said:

Yes pin 31 is correct on the 330, this is a mutual supression pulse that inhibits transmission of the "other" unit so they do not transmit at the same time and cause interference with each other.

Click to expand...

Thanks for the timely response. Last bit of info I needed before diving under the panel.

Pin 35

Correct on the pins, however as I understand it there is no requirement for this line. I didn't run it and Bill @ NavWorx basically said you it's really not necessary but if you want to be able to say sometime in the future you have a suppression line you can!

Regards,

DWS
N142DS

Beware that a transponder Suppression I/O line is used to inhibit the transponder from replying when either a TCAS or DME equipment is transmitting. Only FAA approved equipment can be connected to this line or you may risk ATC not receiving your transponder reply or erratic DME operation. Navworx products are not FAA approved according to the FAA website records.

Pepe

Suppression line

Pepe:

Thanks for your comments about the suppression signal. I was finishing my install today for the transponder control modification. I was planning to connect the suppression line but will now will not. Will leave the pins in place if it ever becomes required. Again, thanks for your comments.

Unlike XM which uses 2300MHz ADS-B/UAT operates on the DME band at 978 MHz. This causes the UAT link to be corrupted at times by transmissions from the onboard DME. The result is WX data missed. This causes delays on the WX update and traffic. For better UAT link performance turn off the onboard DME. The onboard transponder also causes interference but to a lesser degree unless you are in view of multiple radar sites. The above explains different performance experiences by UAT users.

Pepe

If you have concerns regarding making this connection, talk to Bill Moffitt at NavWorx. I did and decided to make the connection as was recommended