Replacement Suggestions for King KX-155

I am under the impression from trying to speak with TKM, via email and phone, they are no longer in business. Trig from their website looks to be in business still but is it a slide out the old Kx 155 and slide in the new Trig or do you need a dealer to install?
 
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Emailed KX 155 display not much in the way of giving out information but they are able to replace the readout and fix some minor problems for <$1000
 
I am under the impression from trying to speak with TKM, via email and phone, they are no longer in business.

If some PoA’er would like to visit their location in a retail area near the Scottsdale AZ airport, and see if the office looks occupied, here’s the address
14811 North 73rd Street, Suite #101, Scottsdale, AZ 85260
 
is it a slide out the old Kx 155 and slide in the new Trig or do you need a dealer to install?
No, it's not a slide-in replacement. However, you don't need a dealer to install (unlike Garmin). I believe your friendly neighborhood A&P can do it.
 
If some PoA’er would like to visit their location in a retail area near the Scottsdale AZ airport, and see if the office looks occupied, here’s the address
14811 North 73rd Street, Suite #101, Scottsdale, AZ 85260
Looks like several TFR's will soon be over the airspace, so referring to Google which seems to think they're still around...
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they refuse to manufacture it out of arrogance and pride instead selling a garmin unit which is larger and in some ways inferior.

They did the same thing with the cnx80/gns480. Seems everyone liked the 480 over the 430, but sunsetted the better product when they bought them.
 
Just FYI, I have a ‘newer’ kx-155 that’s working fine. If there was a viable slide in replacement I’d be a serious contender.
 
At least some of those old King card-edge connectors are starting to crumble from age. And, the bonafide King connector pins are getting scarcer and more expensive. It really sucks to have to spend $5k to replace a 50 year old NavCom but there it is. Maybe if you need an updated GPS too, you can just splurge and get a new GTN or IFD.
 
I almost bought a KX155, untill I ran accross a KX125 for the same money. I got the 125, and never even thought about a 155 again.
The 125 does everything the 155 does, plus it has it's own CDI display. Mine also has glideslope because it will interface with the KI214 and KI211 indicators that have internal GS reciever. All in a much smaller package.
 
I almost bought a KX155, untill I ran accross a KX125 for the same money. I got the 125, and never even thought about a 155 again.
The 125 does everything the 155 does, plus it has it's own CDI display. Mine also has glideslope because it will interface with the KI214 and KI211 indicators that have internal GS reciever. All in a much smaller package.
Is the KX125 a slide-in replacement for the KX155? Looking at the specs, I don't see how the KX125 is smaller than the KX155. If anything, looks like the KX125 is 5mm deeper than the KX155.

Also, looks like the KX125 is only 5W transmit while the KX155 is 10W transmit. Interestingly, the KX125 install manual has a warning about limited LCD viewing angles as well.
 
So, what I'm getting from this whole thread is that there are no good options, but maybe the GTR 225 is the most cost effective if you want something new, otherwise just get another KX155 and take your chances on how long it lasts (and even those can approach the cost of the 225, at least the 25khz one which looks like it's about $2.4k at the moment - well, plus installation)...
 
So, what I'm getting from this whole thread is that there are no good options, but maybe the GTR 225 is the most cost effective if you want something new, otherwise just get another KX155 and take your chances on how long it lasts (and even those can approach the cost of the 225, at least the 25khz one which looks like it's about $2.4k at the moment - well, plus installation)...
GTR225 is COM-only. GNC255 is NAV/COM like the KX155. Trig also sells COM-only as well as NAV/COM, both of which are more cost effective than Garmin.
 
True, sorry I didn't mention that -- it looks like the 96 is the Trig comm-only version. For me, COM-only is actually fine, since I am VFR only. NAV is a nice bonus, but not required, and maybe not worth a lot of cash.

So -- depending on your need for NAV, GTR225 or GNC255, or Trig 56a/96a, or roll the dice on yet another used KX155. Seems like that's pretty much it? Other options?
 
True, sorry I didn't mention that -- it looks like the 96 is the Trig comm-only version. For me, COM-only is actually fine, since I am VFR only. NAV is a nice bonus, but not required, and maybe not worth a lot of cash.

So -- depending on your need for NAV, GTR225 or GNC255, or Trig 56a/96a, or roll the dice on yet another used KX155. Seems like that's pretty much it? Other options?
If you want COM-only, you have a whole bunch: GTR200, Trig 91, ICOM, VAL, Becker, Microair, PS-Engineering...
 
https://www.kx155display.com/

Does anyone have any experience with these guys?

Yes. I put the display in my KX155. Its not bad. The instructions to do the work are pretty detailed, but if you arent handy with a soldering iron, it could be a little challenging. I ended up having an issue with mine 6-8 months after I installed it. I emailed the owner and explained what was happening and he suggested a couple things to try. turns out one of my solders was cracked or bad somehow. Anyway, that fixed it and its been fine since. I honestly dont know about the legality of it. The website swears its legal as an "Owner produced part" but then gives references for the lens covers. so idk. I am at the point with my radio that I would rather ask for forgiveness than permission.
 
How much difference does 8W transmitter vs 10W make in actual use, if any? Looking at the Val 2000 also...
 
No practical difference in 8 or 10 watts. Either should be ok.

Depending on the kx-155 you own (24 volt or 14 volt), you can greatly improve the performance of SOME, NOT ALL, by treating plug in IC's and display contacts with Caig Deoxit. I live in NC, it is very humid here compared to other locations...I have fixed kx155's in both my planes by a simple treatment caused by corrosion inside the radio on the pins of plug in IC's and display contacts.

The kx155 is a great navcom when working properly.

The replacement display looks really good...thanks to Wrench978 for info.
 
My complaint about the GNC255 is that the display seems to have a mode that says "I-am-a-COM-radio" displaying only COM info and a mode that says "I-am-a-NAV-radio" displaying only NAV info but not a mode that says "I-am-a-NAV/COM". Say you're on a VOR approach when a COM transmission comes in. Did it come from the active COM frequency? Or did it come from the standby frequency because COM monitor mode was turned on? I don't know because the display is in NAV mode. The Trig is better because it displays both COM info and NAV info side by side.

Also, the GNC255 lacks NAV monitor mode and BC mode, which the older SL30 did have and the Trig also does have. Plus, does the GNC255 really need to be 1.66" tall rather than the 1.33" of the SL30 and the TX56A?

I prefer Garmin EFIS, but make my audio panel a PS-Engineering unit and my NAV/COM Trig.

Pushing T/F will display information about the "other" side of the 255A. I find it to be an excellent COMM radio and backup NAV to a GTN. I've flown at least 1200 hours with a GTN (650 & 750) over a 255A. Just works. That said I saw a Trig equivalent recently and it seemed very nice. I have their tiny -92 series (COMM + Intercom) in a plane and it is spectacular.
 
I currently have two KX-155s -- I think I'm going to pull one and replace it with a Val 2000, for something new and relatively modern but at the easier end of the price range that should hopefully be hassle free for some time. Then I can get the KX-155 that I pulled out cleaned up and refurbished and it can be a spare (or swap it for the other one and get *it* refurbished too, so I should have two cleaned up 155s---one spare---and a modern COM-only).
 
Is the KX125 a slide-in replacement for the KX155? Looking at the specs, I don't see how the KX125 is smaller than the KX155. If anything, looks like the KX125 is 5mm deeper than the KX155.
Not a slide in replacement. 5mm longer? mabe so, but not as tall.

Also, looks like the KX125 is only 5W transmit while the KX155 is 10W transmit. Interestingly, the KX125 install manual has a warning about limited LCD viewing angles as well.
With a good antenna system 5w is plenty.
 
How much did you spend to get your KX125 installed?
Mabe $100 total for wire, connectors, etc. I have experience in electronics, and avionics installation, and work with an A&P/IA who is confident in my work, inspects, and signs the logs. YMMV
 
Mabe $100 total for wire, connectors, etc. I have experience in electronics, and avionics installation, and work with an A&P/IA who is confident in my work, inspects, and signs the logs. YMMV
Nice! Got any pics?
 
Sometimes time just marches on. Get a Garmin GNC-255A and be done with it. Like others have said, rewiring for a new radio isn't that hard or expensive.
 
Yes. I put the display in my KX155. Its not bad. The instructions to do the work are pretty detailed, but if you arent handy with a soldering iron, it could be a little challenging. I ended up having an issue with mine 6-8 months after I installed it. I emailed the owner and explained what was happening and he suggested a couple things to try. turns out one of my solders was cracked or bad somehow. Anyway, that fixed it and its been fine since. I honestly dont know about the legality of it. The website swears its legal as an "Owner produced part" but then gives references for the lens covers. so idk. I am at the point with my radio that I would rather ask for forgiveness than permission.
as to owner produced parts, i bet that would not fly if questioned by the FAA. but who knows. but with all non required equipment its up to the installing A&P as to its airworthness. so,if your ia is ok with it, no problems. the agency that would go ape s..t is the FCC if they ever got hold of it. because it has not been tested in that configuration, the FCC certs are void.
 
Sometimes time just marches on. Get a Garmin GNC-255A and be done with it.
Actually, the GNC255 is already 10 years old. The Trig TX56 being more recent might be a little more future-proof, if that's the concern.
 
Every plane I have owned, including the current one, has had at least one kx155. I agree talk about a missed opportunity for either a slide in replacement or a display overhaul to LED screen.

I skimmed the thread. Are we still mostly out of luck for a replacement? Makes me want to buy another spare.
 
It really is amazing that no one has come to market with a slide in replacement, considering how large the market is.
 
TKM did have a slide-in replacement for KX155 (seen one in the wild) but it cost close to a new Garmin.

Mathematically KX155/165 (1990) ≈ GNC255A (today) in terms of ubiquity.
 
I Can install a new navcomm for you in about 2-3 hours depending on the complexity of your indicator. Some are super fast. HSI’s take quite a bit longer. The Longer time if your connector requires solder and shrink wrap versus crimp- some indicators are solder only.


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I Can install a new navcomm for you in about 2-3 hours depending on the complexity of your indicator. Some are super fast. HSI’s take quite a bit longer.
But the HSI only takes 2 wires. ;)

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Emailed KX 155 display not much in the way of giving out information but they are able to replace the readout and fix some minor problems for <$1000
How legal is their repairs as they are not a FAA approved service provider, they even point that out on their website?
 
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