GTN 650 Installation

edessa

edessa

Pre-takeoff checklist
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edessa
I am reaching out to ask if anyone has installed a GTN 650 (non xi) with an existing King KMA 20 audio panel.
How did the install go and were there any difficulties during installation?
Can it even be done?
Looking at the install manuals for both units it seems like it should work.
The installation will be in a 1976 PA-28-140. Here is the existing panel.
Will be removing the #2 radio, moving the #1 to the #2 spot, removing the Loran system (still works) and installing the GTN 650 with a new GI 106A in the #1 spot.
I would like to upgrade the audio panel but being a non profit we don't have the funds to upgrade all at once.
If anyone wants to donate an audio panel or any other avionics and get a tax write off please PM me.
N4758F panel - Copy.JPG
 
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Yes - that can be done - anything can be done!

Everyone dogs the KMA 20 because it’s old- and it is old. However, it was a good unit in the day and many soldier on today - I just do not recommend making any investment that would “marry” you to it which doing the new GPS install will do.

What’s your intercom- have you quoted a PM8000G with your present plans? Much of an audio panel install involves some of the work involved in installing the 650.

Here are some other ideas.

1. WAAS 430 and new audio panel.

2. Keep TKM as number 1 and new audio panel and I think it’s a GNC375 (com and gps) as number 2.

Good luck - enjoy!
 
MPB said:
Yes - that can be done - anything can be done!

Everyone dogs the KMA 20 because it’s old- and it is old. However, it was a good unit in the day and many soldier on today - I just do not recommend making any investment that would “marry” you to it which doing the new GPS install will do.

What’s your intercom- have you quoted a PM8000G with your present plans? Much of an audio panel install involves some of the work involved in installing the 650.

Here are some other ideas.

1. WAAS 430 and new audio panel.

2. Keep TKM as number 1 and new audio panel and I think it’s a GNC375 (com and gps) as number 2.

Good luck - enjoy!
Click to expand...
Thank you for the reply.
I agree the KMA 20 is very old and needs to go.
We have the GTN 650 and GI 106A ordered and on the way.
Unfortunately I can only recommend and install the parts in the aircraft. I don't pay the bills.
I have recommended replacing the audio panel since we are diving into everything but no funds are available.
Since I work for the non profit they don't have to pay outside installation costs.
I have thought of buying and donating a GMA 340 or 345 but I have already donated and installed the Stratus ESG this year.
 
As before the KMA20 is old but not a bad unit - I've got one and plan to switch it for a PMA8000G when it quits - problem (I suppose) is that it will not give up the ghost and I refuse to spend the 4 to 5 AMUs until then.

How about your intercom - that's really critical in this discussion - I've got a PMA3000 and its the same quality as what's in the 8000 so that's taking the heat off me in terms of the KMA20. If you do not have a good intercom the audio panel becomes a bigger issue.

I feel pretty strongly on this - if you are going to spend the money on the 650 install please figure out a way to do that audio panel. When the trusty KMA20 dies - which it eventually will - you are going to have to redo some of the stuff you are paying for with today's 650 install.
 
Sorry I don't read things as good as I used to - I see now install costs are not the issue since you'll be doing the install as an employee.
 
Part of this is to have the students we support, learn about aviation by helping work on the Cherokee and by us paying for their flight training and hopefully have their private license by the time they graduate high school.
 
I'd move heaven and earth to figure out how to come up with an extra $1k or so for a new audio panel. It will cost way more to go back and do that work later.
 
My airplane has a KMA-24 with a 650Xi (used to be a non-Xi). Works fine.

Audio panels only handles audio signals and controls the connection of the PTT. Pretty much universal.
 
edessa said:
I am reaching out to ask if anyone has installed a GTN 650 (non xi) with an existing King KMA 20 audio panel.
How did the install go and were there any difficulties during installation?
Can it even be done?
Looking at the install manuals for both units it seems like it should work.
The installation will be in a 1977 PPA-28-140. Here is the existing panel.
Will be removing the #2 radio, moving the #1 to the #2 spot, removing the Loran system (still works) and installing the GTN 650 with a new GI 106A in the #1 spot.
I would like to upgrade the audio panel but being a non profit we don't have the funds to upgrade all at once.
If anyone wants to donate an audio panel or any other avionics and get a tax write off please PM me.
View attachment 118904
Click to expand...
My buddy had a g175 and a I275 installed in his cherokee 140 with a KMA24.
(edited)_IMG_9563(1).png
 
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Seriously, once you've used a crystal clear full stereo PS-450B or PS-450C you'll curse flying a plane with a KMA-20 or KMA-24. The clarity and features are another realm by comparison. Almost a crime to install a GTN-650 and leave a KMA audio panel in place.
 
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NordicDave said:
Seriously, once you've used a crystal clear full stereo PS-450B or PS-450C you'll curse flying a plane with a KMA-20 or KMA-24. The clarity and features are another realm by comparison. Almost a crime to install a GTN-650 and leave a KMA audio panel in place.
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I want nothing more than to replace the audio panel and/or upgrade the entire panel. Unfortunately the reality is that we can’t afford it at this time. I have reached out to several OEMs and avionics shops asking to donate/partner (tax deductible) with us but haven’t heard back from anyone yet. The GPS and indicator should be delivered late this coming week to early the following week.
 
edessa said:
I want nothing more than to replace the audio panel and/or upgrade the entire panel. Unfortunately the reality is that we can’t afford it at this time. I have reached out to several OEMs and avionics shops asking to donate/partner (tax deductible) with us but haven’t heard back from anyone yet. The GPS and indicator should be delivered late this coming week to early the following week.
Click to expand...

Completely understand running against an absolute dollar limit. Congrats on the install of a 650.
 
If you're planning on replacing it anyway do it all at once if possible. Less labor/wiring that way. OTOH if you're perfectly happy with the audio panel IDK if I'd want to spend the money. I had one of those in my Archer and it worked just fine. The Lance I fly now has a newer GMA 340 audio panel which looks nicer for sure but really I'm just using the in-plane intercom and calling ATC... turning COM2 on and off and now and then hitting isolate if my kid is getting too noisy in the back. How fancy does your audio panel really need to be?
 
Gma340/pma8000 used? $550-1000.

Buy yourself a healthy amount of 27500 22g /3c on eBay along with 22759/22g.

Many shops charge 2000-2500 for an audio panel install, but you can do it if you wish and have your IA sign it off. I collect proposals from shops that only install the new equipment they sell. Ideally you get an audio panel with an 8130 - part 145 shops have to bring it into their inventory and blah blah blah so it’s difficult.

We build those harnesses in-house.
 
Llk said:
Gma340/pma8000 used? $550-1000.

Buy yourself a healthy amount of 27500 22g /3c on eBay along with 22759/22g.

Many shops charge 2000-2500 for an audio panel install, but you can do it if you wish and have your IA sign it off. I collect proposals from shops that only install the new equipment they sell. Ideally you get an audio panel with an 8130 - part 145 shops have to bring it into their inventory and blah blah blah so it’s difficult.

We build those harnesses in-house.
Click to expand...
I will have my students install everything under my supervision (I'm and A&P and I.A.) as part of one of their school projects. No need for outside shops.
More than likely I will be installing a new PMA6000B.
Click on the Argonaut link in my signature below for more info on what we do and to support if you would like.
 
MPB said:
Yes - that can be done - anything can be done!

Everyone dogs the KMA 20 because it’s old- and it is old. However, it was a good unit in the day and many soldier on today - I just do not recommend making any investment that would “marry” you to it which doing the new GPS install will do.

What’s your intercom- have you quoted a PM8000G with your present plans? Much of an audio panel install involves some of the work involved in installing the 650.

Here are some other ideas.

1. WAAS 430 and new audio panel.

2. Keep TKM as number 1 and new audio panel and I think it’s a GNC375 (com and gps) as number 2.

Good luck - enjoy!
Click to expand...
430? bad idea. they have not been made for almost 15 years and the parts supply is almost gone. when that happens its a boat anchor if it needs service. it was a great unit, but its days are over. a new install of one is a foolish idea.
 
unsafervguy said:
430? bad idea. they have not been made for almost 15 years and the parts supply is almost gone. when that happens its a boat anchor if it needs service. it was a great unit, but its days are over. a new install of one is a foolish idea.
Click to expand...
Actually, as I understand it, what’s running out are out of production integrated chips which rarely fail on these units. Thus, some repairs will increasingly become impossible but most should still be doable for years to come. They’ve sold over 120,000 of these units so I do not think they’ll be boat anchors just yet - I’m amazed by the number of Silver Crown boxes still soldiering on - lots of that stuff is from the 70s, 80s, and 90s.

However, do agree 430 is suboptimal - unfortunately, in a world of limited bucks you’ve got to do what you’ve got to do.
 
MPB said:
However, do agree 430 is suboptimal - unfortunately, in a world of limited bucks you’ve got to do what you’ve got to do.
Click to expand...

There’s way to cut costs, but that’s not one of them.
 
Pinecone said:
They are about out of displays.
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spot on. Also, garmin has never released the manuals and schematics for them, so when garmin stops supporting them it’s game over. Unlike the thru hold designs of the 70’s, 80’s and 90’s, those units are high density surface mount, you dont just fix the board, you replace it. Without farming support it’s end of life when it stops working.
they have supported them for what, 15 years sine the end of production? That’s a great record, but its about to end, sooner than later.
,
 
I am sure there will be a cottage industry buying bad units to cannibalize the working parts. But unfortunately, the parts that fail tend to be the same parts, so non-working ones don't have the required working parts to fix others.

Long term support is why I swapped my 650 for a 650Xi when Sarasota Avionics was offering a deal to do so.
 
Noticed the older kx175b radio too.
Here is another possible option if expense is the main focus of your upgrades. You do lose 1 NAV, screen size, and some other small options not going with the 650, but it depends on exactly what functionality you are looking for really.

PAR200B ($3095), with Garmin GPS175 ($4995)
That gets a new audio panel, GPS, and new comm radio, and some right panel space (remove kx175b) for around $8,000. Not sure on install cost.
The 650 ($12,000) will have NAV, but is several AMU's more, and no audio panel, plus installation of course.

Not a recommendation, just an option.
(edit: all prices from sarasota avionics)
 
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Skyrys62 said:
Noticed the older kx175b radio too.
Here is another possible option if expense is the main focus of your upgrades. You do lose 1 NAV, screen size, and some other small options not going with the 650, but it depends on exactly what functionality you are looking for really.

PAR200B ($3095), with Garmin GPS175 ($4995)
That gets a new audio panel, GPS, and new comm radio, and some right panel space (remove kx175b) for around $8,000. Not sure on install cost.
The 650 ($12,000) will have NAV, but is several AMU's more, and no audio panel, plus installation of course.

Not a recommendation, just an option.
(edit: all prices from sarasota avionics)
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This is the way. Who needs two NAVs in 2023, really?

Personally I'd prefer the radio in a GNC355 instead of in the audio panel (mostly because I have a PMA450 and love having the screen dedicated to audio).
 
Eric Pauley said:
This is the way. Who needs two NAVs in 2023, really?

Personally I'd prefer the radio in a GNC355 instead of in the audio panel (mostly because I have a PMA450 and love having the screen dedicated to audio).
Click to expand...
Personally, I'd prefer the radio to not be in the GNC355 because that frees up the right knobs for menus rather than being dedicated to COM tuning. Plus, it frees up an on-screen data field for something other than frequency display. I would think I'd be looking at the GPS screen more often than the audio panel screen.

But to each their own.
 
I have everything I need for the installation of the audio control panel and the GTN650. My CFI check ride is on December 8 so after that I will ground the airplane and have two or three of my students help me install it.

IMG_8405.jpeg
 
Congrats. That will be a very nice upgrade.

C.
 
Well weather did not cooperate. Had my oral for the CFI on December 8th and didn’t finish the flight portion until February 3rd.
Started the annual on the Cherokee this week with my students. Part of the job is to install the new avionics. Here is the one day progress.IMG_8643.jpegIMG_8642.jpegScreenshot 2024-03-19 at 08.13.47.jpeg
 
The prop being off looks like your avionics money being tugged on.

Looking forward to some ugly spaghetti wire pics next…
 
455 Bravo Uniform said:
The prop being off looks like your avionics money being tugged on.

Looking forward to some ugly spaghetti wire pics next…
Click to expand...
Yeah, that will be fun.
Today we did take out the trays but left the back plates in the airplane. Concentrated on jacking the plane and going through the wheels, brakes, and landing inspection. Tomorrow we will start removing the old wires and back plates in preparation of installing the new avionics.
One thing I wont do is just cut wires and pull boxes. Looks like it's happened a few times over the years as there are a few wires that were cut and just left in the plane. Good time to clean all that up.
 
Todays progress. Started by closing up wing panels, replacing ELT batteries and testing ELT.
Removed all trays except for one and removed all back plates and wires except for one.
Will start install of new avionics tomorrow.IMG_8654.jpegIMG_8652.jpeg
 
More wires are soon to come out as I removed the old intercom. Installed the tray and test fit the audio control panel.
Waiting on parts to arrive from Aircraft Spruce on Monday to continue.IMG_8656.jpeg
 
Just read through all of the back and forth here. As someone who is still a bit of a nearby to all this I find all the technical stuff quite fascinating indeed….
 
When I did my upgrade to GTN, my shop replaced GPS antenna and wiring, I don’t remember if it was required or they just insisted as a matter of policy.
 
Continuing with the avionics installation this week. Started on Monday with the GTN tray and harness install. Today we wired the audio control harness to the MX170C and fabricated the doubler for the GPS antenna. Things are going slower than I would like due to students being around and having to stop what I'm doing to show them how to use tools and install panels.
IMG_8672.jpeg
 
Made some progress today. Installed the GPS antenna doubler and started terminating wires. I fabricated a panel for the new avionics master switch and new circuit breakers.
IMG_8673.jpeg
 
Finally had power on yesterday. All in all a good install. A couple of issues. One being I have a red X on the NAV and the NAV software shows _.__. I do have an older NAV splitter that is not compatible with the GTN but I can't confirm that is what is causing the red X on the NAV. I have the correct splitter ordered.
The other issue is that I can't hear the other passengers in the aircraft through the headset. COM on 1 and 2 come in fine and NAV 2 voice is fine. Before I called it a day I saw a couple of pins pushed back on the audio panel plug.
Pay no attention to the poorly painted C/B panel. This is what you get when you use old paint to save a couple of bucks, I just have it installed with one screw to test the system. I will re make the panel and use new paint.
IMG_8675.jpegIMG_8678.jpeg
 
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