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-   -   Navworx , back in business? (https://vansairforce.net/community/showthread.php?t=149343)

DavidBunin 05-27-2017 03:07 PM

Well Bill is the expert, so if what he says diverges from whatever I post here, I encourage you to ignore me.

Flight ID should be the tail number unless you are operating with an official ATC call sign (such as a charity flight or life flight). The only exception I can think of is if operating in anonymous mode. A code of 1200 would push my thoughts in that direction, but then when you change to a discrete code I would expect the Flight ID to go back to being your tail number.

The UAT should have your tail number programmed as a constant within the maintenance console. Might want to check that field.

While you're at it, may as well make sure that your SL70 has your tail number programmed correctly.

recapen 05-27-2017 03:21 PM

Thanks David - I did check the UAT and it had my tail number correct.

The SL-70 cannot be programmed with any data. The squawk code (1200 for VFR and as assigned by ATC) which I was referring to earlier is supposed to be sent from the SL-70 where it is set to the ADS600B for transmission along with the other info as the SL-70 is suppressed by pin 35 of the ADS600B. The FID I referred to was displayed in my MX20 (data sent to it by the ADS600B) which prompted me to look in the data stream (in the UAT console)...The data stream also shows my tail number correctly (from the ADS600B) and the 1200 - which did not change when I changed the setting in the SL-70. I think FID might be a misnomer from the MX20.

Hope that clears the mud

Not ignoring anyone - trying to learn as much as I can!

DavidBunin 05-28-2017 06:50 AM

Interesting. I thought the SL-70 was a Mode S transponder, but maybe it isn't.

I know with a TransMON it takes a certain number of replies before the UAT changes to the new squawk code. Sometimes as long as 15 seconds. It's not immediate.

I don't know if that behavior is the same when using a databus connection. In other words, I don't know if the delay is a factor in the TransMON itself, or an internal characteristic of the UAT.

As posted above, these systems work best when the transponder is replying to interrogations. What do you observe in the Flight ID during flight?

Jesse 05-28-2017 06:58 AM

Quote:

Originally Posted by DavidBunin (Post 1176077)
Interesting. I thought the SL-70 was a Mode S transponder, but maybe it isn't.

I know with a TransMON it takes a certain number of replies before the UAT changes to the new squawk code. Sometimes as long as 15 seconds. It's not immediate.

I don't know if that behavior is the same when using a databus connection. In other words, I don't know if the delay is a factor in the TransMON itself, or an internal characteristic of the UAT.

As posted above, these systems work best when the transponder is replying to interrogations. What do you observe in the Flight ID during flight?

The SL-70 is a Mode C transponder. It differs from the GTX-327 in that it outputs both the squawk and the altitude (even if it gets the altitude from a Gray code encoder) via the RS-232. The GTX-327 outputs squawk, but you still need the altitude, so if you don't have an encoder that has RS232 output, you still need the Transmon. This information is from experience re the 327 and from Bill re the SL-70.

recapen 05-28-2017 07:30 AM

I have my SL-70 installed and functioning the way Jesse describes - gray code in to the SL-70 and serial out.

I haven't flown it yet to answer David's point but will wander down to some flight following where they issue me a different squawk code - we'll see what happens then!

Can we get Bill to chime in?!

recapen 05-30-2017 03:44 PM

Bill responded to my request for help with a couple of things to check.

One possibility is that my MX-20 is set up as the controller instead of the SL-70. Gotta figure out where that setting is and change if it is wrong! Then I can check the status field.

Status update next weekend when I get to the hangar to try it out!

dtw_rv6 05-30-2017 08:23 PM

Quote:

Originally Posted by Jesse (Post 1176078)
The SL-70 is a Mode C transponder. It differs from the GTX-327 in that it outputs both the squawk and the altitude (even if it gets the altitude from a Gray code encoder) via the RS-232. The GTX-327 outputs squawk, but you still need the altitude, so if you don't have an encoder that has RS232 output, you still need the Transmon. This information is from experience re the 327 and from Bill re the SL-70.

Not sure if I'm talking apples to apples, but my GTX327 is sending ialtitude and squawk to my EXP. At least until I switch the transponder to standby and my UAT stops transmitting. Not sure how I'm going to handle that since we aren't supposed to switch off adsb even when transponder is in standby for formation

DavidBunin 06-03-2017 03:02 PM

Quote:

Originally Posted by dtw_rv6 (Post 1176860)
my GTX327 is sending altitude and squawk to my EXP. At least until I switch the transponder to standby and my UAT stops transmitting.

Only if you're using a TransMON device.

If you don't have a TransMON, the GTX327 only has one data output port and it can only output one data format (squawk or altitude, not both).

Possible that you have the control data (squawk) coming to the UAT from your GTX327 and you have the altitude from your encoder going into the UAT directly (and into the GTX). Or possibly you have the TransMON.

The NavWorx UAT does not stop transmitting when you turn your transponder off. It simply transmits a message that says there is no control input data. So you are still in compliance with the rule.

roadrunner20 06-03-2017 04:00 PM

Quote:

Originally Posted by DavidBunin (Post 1177847)
Only if you're using a TransMON device.

If you don't have a TransMON, the GTX327 only has one data output port and it can only output one data format (squawk or altitude, not both).

Possible that you have the control data (squawk) coming to the UAT from your GTX327 and you have the altitude from your encoder going into the UAT directly (and into the GTX). Or possibly you have the TransMON.

The NavWorx UAT does not stop transmitting when you turn your transponder off. It simply transmits a message that says there is no control input data. So you are still in compliance with the rule.

David, I believe you're correct in that altitude is received from the encoder & the GTX transmits squawk control data. When I originally set up my UAT, I had expected both from the GTX, but had to T off from the encoder to the GTX & UAT box.

dtw_rv6 06-03-2017 05:28 PM

You guys are correct. I wired this up two years ago and I've already forgotten.

How do you know the UAT is still transmitting when the transponder is in standby? I don't appear on my buddy's foreflight when I'm not squawking.


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