Club Homepage Forums Classified Ads Buy & Sell - Everything But Airplanes Looking for R-443B (Maybe)

OK, so as I posted above, we have similar panels. I have a glideslope on my MX300, though. If I wanted to spend the money once and get ILS functionality combined with GPS IFR capability, here's what I would do in your case.

Because you have a modern transponder, no need to change that.

I'd install a GNC 355 with some sort of indicator or tie-in to HSI (more on this later*). This would give you a modern Com and gps.
I'd go on ebay or elsewhere and get a ARC glideslope CDI and r-443b and connect it to the mx300. (not sure what model CDI you need, Ask an old school avionics guy)
https://www.ebay.com/itm/266927099679
https://www.ebay.com/itm/266970279757



You can do many options for the GPS indicator....one is find a used gi-106a or 106b ($800-1500, if lucky). Another option is to install a new gi275 as a MFD/CDI (but that's getting up in $$$).

Are there any ILS approaches around you? It may not be worth the effort to get glideslope.

A modern NAV/COM will be $4-5k for the transciever + install + CDI. A modern COM alone is $1500-2000.

*If you end up getting a gi275MFD, getting a GNX 375 will get you traffic in on your MFD and your ipad. You could sell/trade your stratus Xponder, but now you are back to just the MX300 only for a Com.


I've been through the various permutations on how to solve getting IFR GPS in my 150 and I can't really come up with anything less than $15,000-20,000 to do it right and make it worthwhile.

Thanks man for all the info and details!!

It’s so easy to get out of hand with all this stuff. Just trying stay on a progressive path and not spend a bunch of money and put myself in a corner where it cost more to back out of.

And we still have some old school approaches around me (a lot of decommissioned military bases), but the overwhelming amount is obviously RNAVs.

Attached is the current panel. Not sure what model CDI this is, and what can talk to it.

Hmm, I don't see an audio panel. Also, the picture is small, but are there two flags/needles on the CDI (horz and vertical)?

Here's a valid article I just came across regarding IFR flights using VFR GPS. https://www.flyingmag.com/technique-tip-week-it-permissible-use-vfr-only-gps-while-flying-ifr/

No audio panel. That's actually the first on my list, because I don't have a panel mounted intercom either. A portable works, but i can do without the wires and "mess". I also like the idea of having Bluetooth connectivity through the intercom and not relying on the headsets.


I like the PS Engineering PAR200B, with the remote mounted Trig radio, obviously for space. So in the meantime, adding just that will give me an intercom, 2nd Radio, and audio panel in one install.

Next will likely be an engine monitor. I'd love to more easily control fuel flow, leaning, etc.



Looking at the photos, the CDI appears to be an ARC 525, from a fair amount of Google Lens searches.



After considering your input and advice, the MX300 will likely see out its better days as a COM, and horizontal NAV only. The money I will likely spend on 50 year old equipment and installation may not get me very far into newer avionics, but at I figured at least I'm not going backwards.

Next step will be replacing the MX300 with some sort of GPS NAV/COMM, or GPS COMM. Another one of your comments mentioned non GPS Approaches etc. We still have several around, but almost all are coupled with RNAVS. I can take the money it will cost to get a NAV Radio and put it toward another GI275 to eliminate steam gauges or engine gauges.

The Garmin 430/530 used market seems to be ideal for a stepping stone, and if i went with GI275, the HSI/CDI wouldn't need to be changed for a future upgrade. But by the time I get all these finances in line, the GNC355 and the GTN 650 will already be "yesterdays news". So who knows.

I really appreciate your input and advice. It really got me aligned before I through some money at a "quick fix".

I'm not sure who I'm kidding anyways, I have 3 daughters, aged 13,11, and 8. So i don't see Garmin having any large amount of my money anytime soon. HAHAHA

Bingo. I don't have any nav in my airplane because I don't fly in the clouds anymore. But when I was looking for a second radio I picked the PAR200. Audio Panel, Radio, and Intercom all in one is perfect. It also adds Bluetooth reception so I can listen to my music.



That would be a great upgrade. Get rid of all that stuff over on the right panel.

Well with the Tach already off a little, I figure I might as well just bite the bullet. In the perfect world where money isn't a problem, I'll have 3 GI 275s that will take care of every gauge in the cockpit.

I'm hoping to have the ability to fly in the clouds, but I don't think that the money for NAV needs to come before valuable VFR upgrades (since it will be 95% or more of my flying).

And yes, the Bluetooth in the intercom eliminates the need for every headset to have Bluetooth, which can be a mess trying to connect.

Buy a EI CGR-30P and eliminate all the OEM gauges except for the vacuum gauge. BUY 2 AV-30's and get rid of the vacuum system...

I'm surely in the minority, but I'm not seeing the value in getting rid of original engine gauges when we are speaking of a limited budget. I always aim for low hanging fruit first. If the tach isn't reading right, I think a few hundred bucks max can get it overhauled. $4k plus install for an engine monitor seems a bit unnecessary to me. The o-200 is pretty lightly loaded and not stressed. Many go 3000+hours with no engine monitors, so what are you gaining?

And I still see vacuum gyro overhauls for under $300-500? We're talking about keeping a small trainer plane flying as cost effectively as possible. Why drop 50% of the plane value in a panel?

Back to the original question of this thread, a R-443b can be had for $100 or less off ebay. The plane may already have a CDI/Glideslope indicator installed. He has a compatible MX300. The only unknown here is wiring and man-hours required to install a r443b for being able to shoot ILS approaches. Maybe an entire bundle of wires from another c150 can be found and it's almost plug and play (thus getting 5-10man hours install?) That seems like a pretty good value preposition with a good gain of function (assuming you have some ILS approaches around the home field).

Next gain of function is IFR GPS......which I've discussed a lot in some other threads (search my posts).

After the IFR GPS, then I'd attack elimination of vacuum gyros. Again, this is all in the perspective of we are talking about a c150 that has 2.5hours of endurance lol

Trust me. I’m hearing you! This “plan” changes by the hour. But at the end of the day, if I had to choose between shiny thingies in the dash, or airplane gas, we gonna fly

Even overhauled tachs have a 200 to 400 rpm error!!! That is why you get an electric tach! I have replaced the mechanical tach for a new electric tach in about 12 planes now. EACH owner says, "Why didn't I do this sooner!"

You can get a stand alone EI R-1 electric tach for about $400.00. You spend almost that much for an overhaul on your outdated mechanical tach! Do the math again...