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KLN-89B for ADS-B OUT?

chris mitchell

Well Known Member
I have just replaced an old KT76A transponder with a Trig TT-31, to provide a mode S device. It occurs to me that I could also enable ADS-B by connecting the TT31 to a suitable GPS.

The aircraft has both a Flymap L and a KLN89B. The Flymap can be used but would need more software (about USD400).

So I wondered about the KLN89B. It has RS232 ports in and out. What I don't know is whether it will output data in a format that the Trig can use?

The alternatives are:

Do nothing until its mandated; - impact on safety;
Get another GPS to replace the KLN89 B (which is rather old); - cost;
Stump up the cash for the software update on the Flymap; - cost;
Wait for the Trig TN72 (a standalone GPS unit specifically to provide the ADSB function); - cost (probably around 5-600USD);

So - if the KLN89B can do the job, for the cost of 2 feet of wire and a few connectors, its my preferred solution. If any knows or better still has actually done it, I'd be grateful for details.

Many thanks

Chris
 
Hi Chris,

The KLN-89B isn't WAAS-capable so it's virtually certain that it won't meet the GPS accuracy and integrity requirements for ADS-B Out. As far as I know, Honeywell doesn't have an upgrade path to add WAAS to the 89B so you might want to look at other options.

Hope this helps,

Dave
 
Hi Chris,
Dave is correct. The important part is that your GPS or position source must be WAAS capable. Its one of the reasons why folks are getting rid of their GNS 430's (non-WAAS) and opting to go with another solution. Your other option would be to use something like the Garmin GDL 82 that will give you WAAS positioning (for ADSB purposes only) and will work with your existing transponder for ADSB out. If you are just looking for WAAS GPS position source only, you will need something like the GPS 20A (these are just some of the Garmin products that I know, I'm sure there are many other companies that provide similar solutions).
 
You?ll notice that we are all quoting US rules. In the UK they may be different, so you?ll need to do some research. For example, in the US the GRT ?2020? GPS is an approved position source for the TT31 and ADSB-out ($500 USD). But the approval is thru GRT and ?meets the performance standards?. It does not carry a TSO. Is that okay in the UK? I don?t know.
 
question regarding adsb out

my panel has a garmin 430w with a kln 89b gps, what else is needed to be compliant for adsb out requirements?
thanks rv8
 
question regarding adsb out

my panel has a garmin 430w with a kln 89b gps, what else is needed to be compliant for adsb out requirements?
thanks rv8

Your 430W is an approved position source (you may need a software upgrade if you haven’t had one for a few years. See if your box will output format ADSB+). You need a transmitter, one that can accept that format. One approach is to get a new mode-SES transponder that reads ADSB+. Any Garmin box, or a Trig TT-22 or -31 will work. Or, if your current transponder is in good shape, you could look for a UAT. Many options, you need to decide what is best for your situation.
 
Your 430W is an approved position source (you may need a software upgrade if you haven?t had one for a few years. See if your box will output format ADSB+). You need a transmitter, one that can accept that format. One approach is to get a new mode-SES transponder that reads ADSB+. Any Garmin box, or a Trig TT-22 or -31 will work. Or, if your current transponder is in good shape, you could look for a UAT. Many options, you need to decide what is best for your situation.

txs for the response i forgot to add that i have a bendix king 76c transponder in addition to the garmin 430W so should i get the garmin 20a to be compliant? i called stein air and could not get a straight answer
thanks for responding
sorry to ask other question in the same subject the above relates to my IVP but my rv8 has a g3x and a gtn 650 and i am unable to get an adsb out signal also confused about what is required, stein air said that with both i should be able to get a signal but i had the ground test done and got no signal
thanks

andres
 
txs for the response i forgot to add that i have a bendix king 76c transponder in addition to the garmin 430W so should i get the garmin 20a to be compliant? i called stein air and could not get a straight answer
thanks for responding
sorry to ask other question in the same subject the above relates to my IVP but my rv8 has a g3x and a gtn 650 and i am unable to get an adsb out signal also confused about what is required, stein air said that with both i should be able to get a signal but i had the ground test done and got no signal
thanks

andres

Remember you're asking on a forum where the majority are in the USA and the ADS-B rules are different than where you are.
 
Carlos: OP was from England but current questioner lists TX as home.
Andre: You sound confused. You?re not alone.
ADSB-out in the US (now required in class B,C, inside mode C veil, above 10,000?): you have two choices.
1. Buy a new mode S-ES transponder (your kt76c is getting a bit old??). Your G430W and GTN navigators can feed the transponder the required position data, if the new transponder can ?read? Garmin?s proprietary format (ADSB+).
2. Buy a UAT transmitter, operating on 978 MHz. Keep the kt76c. Either buy a UAT that is compatible with adsb+, or get a complete combo UAT-gps. The gps cannot be any old unit, it needs to be ?approved?. The UAT will need its own antenna.
3. ADSB-in is not required, but useful. Many UATs include an -in receiver, some don?t. Most mode SES transponders do not have a receiver included. Make sure the -in box is compatible with however you intend to display the data.
So while you currently own two gps boxes (430W and GTN) that can supply the data, it appears you have no transmitter, mode SES transponder or UAT.
 
Carlos: OP was from England but current questioner lists TX as home.
Andre: You sound confused. You’re not alone.
ADSB-out in the US (now required in class B,C, inside mode C veil, above 10,000’): you have two choices.
1. Buy a new mode S-ES transponder (your kt76c is getting a bit old??). Your G430W and GTN navigators can feed the transponder the required position data, if the new transponder can ‘read’ Garmin’s proprietary format (ADSB+).
2. Buy a UAT transmitter, operating on 978 MHz. Keep the kt76c. Either buy a UAT that is compatible with adsb+, or get a complete combo UAT-gps. The gps cannot be any old unit, it needs to be ‘approved’. The UAT will need its own antenna.
3. ADSB-in is not required, but useful. Many UATs include an -in receiver, some don’t. Most mode SES transponders do not have a receiver included. Make sure the -in box is compatible with however you intend to display the data.
So while you currently own two gps boxes (430W and GTN) that can supply the data, it appears you have no transmitter, mode SES transponder or UAT.


Soppy s for the response
I have adsb in with this setup so I am sure there is a transponder capable inside but seems like adding a garmin 20A might be the best solution

Thanks a lot sounds like maybe the garmin 20a May be the cheapest solution in this situation
 
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NO. The Garmin 20A is an approved gps position source. You don?t need that. Either your 430W or GTN- can furnish the position via an RS232 output. You need the actual transmitter. Either a new mode S-ES transponder that can accept Garmin data (I know Garmin and Trig TT20 and TT31 will), or a UAT transmitter on 978 MHz that can read Garmin?s ADSB+ format.
 
txs for the response i forgot to add that i have a bendix king 76c transponder in addition to the garmin 430W so should i get the garmin 20a to be compliant? i called stein air and could not get a straight answer
thanks for responding
As Bob posted, no.

But another option is, since you have a KT76, you can replace it with a KT 74 and use your G430W as the position source. The KT74 is plug n play compatible with the KT76 so all you would need is to run one small wire from the G430W to the KT74 and configure it correctly. A significant reduction to the installation cost and time.

sorry to ask other question in the same subject the above relates to my IVP but my rv8 has a g3x and a gtn 650 and i am unable to get an adsb out signal also confused about what is required, stein air said that with both i should be able to get a signal but i had the ground test done and got no signal
thanks
It should work so this is a good question for G3xpert.

:cool:
 
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