[rvmills]

I viewed the recent intercom thread in this section...great thread that hits on a issue I'm working through now...didn't want to hijack the other gent's thread, so starting a new one.

I'm in the midst of a panel upgrade plan (D/N VFR X-C panel), and am weighing a PS PM4000 vs. a Garmin GMA 340 Audio Panel. I currently have a PM2000 with audio inputs from a Tera comm, a Garmin 396 (GPWS, etc.), and XM Radio. All inputs and VOX intercom have been very good to date.

For the new panel, the plan is to have audio inputs from a Garmin SL-40, the -396, the XM, and will be adding Dynon D100 warnings/AOA, a Monroy Traffic Watch and a second comm radio that is non-aviation (for comm with a local Sheriff SAR group I'm rushing...it's a Kenwood that I've been told needs an impedence correction to feed to the PM4000, while the comm 3 input on the GMA 340 can take the input directly, as that port has automatic internal impedence correction...one member is using it with success, another has the PM4000 and needed some sort of impedence correction).

My questions are:

For Mark Scheuer of PS (and thanks for the input on the other thread!), the PM4000 has the nice features of being able to monitor and/or transmit on 2 comms as well as separate pilot/copilot volumes (and it costs less than the 340).

Can it handle all the above inputs effectively?
Would you recommend it for use in an RV?
Any thoughts on the impedence issue (I don't have the Kenwood model number, but it is the radio the ground responders have in their vehicles).

For others that have used the GMA 340, it seems it has the capability to handle multiple inputs, per the spec sheet, and can handle the separate comms. Any feedback on the 340's abilities and performance would be greatly appreciated. Also, any positive or negative feedback on the 340's intercom capability would be welcome as well.

Thanks Much!
Bob

"Rocket" RV-6
N600SS
4SD

 

[mscheuer]

PMA4000

Good Morning Bob:

First, I want to alert you that the statement "while the comm 3 input on the GMA 340 can take the input directly, as that port has automatic internal impedence correction" is not correct to the best of my knowledge.

All of the Com inputs in the GMA340 are the same. There are no special "circuits" associated with Com 3. So, you will also need a Tactical Radio Adapter for it too.

Since you are planning on just two radios (SL-40 and the Kenwood), either audio panel can handle the radios (with a Tactical Radio Adapter. This adapter will also provide sidetone for that radio - http://ps-engineering.com/docs/radio_adapter.pdf)

The PMA4000 has four unswitched inputs (GMA340 has two) which would cover all of your unswitched audio requirements.

When we were developing the PMA4000 the code name for the project was "Scappoose" because of Mr. VanGrunsven's connection with that airport in Oregon, so YES, the PMA4000 really is a great choice for your aircraft.

Finally, if for some reason you are still leaning to the GMA340, you might consider looking at the advantages of the PMA8000B (http://ps-engineering.com/compare.shtml)

Mark Scheuer
PS Engineering

I viewed the recent intercom thread in this section...great thread that hits on a issue I'm working through now...didn't want to hijack the other gent's thread, so starting a new one.

I'm in the midst of a panel upgrade plan (D/N VFR X-C panel), and am weighing a PS PM4000 vs. a Garmin GMA 340 Audio Panel. I currently have a PM2000 with audio inputs from a Tera comm, a Garmin 396 (GPWS, etc.), and XM Radio. All inputs and VOX intercom have been very good to date.

For the new panel, the plan is to have audio inputs from a Garmin SL-40, the -396, the XM, and will be adding Dynon D100 warnings/AOA, a Monroy Traffic Watch and a second comm radio that is non-aviation (for comm with a local Sheriff SAR group I'm rushing...it's a Kenwood that I've been told needs an impedence correction to feed to the PM4000, while the comm 3 input on the GMA 340 can take the input directly, as that port has automatic internal impedence correction...one member is using it with success, another has the PM4000 and needed some sort of impedence correction).

My questions are:

For Mark Scheuer of PS (and thanks for the input on the other thread!), the PM4000 has the nice features of being able to monitor and/or transmit on 2 comms as well as separate pilot/copilot volumes (and it costs less than the 340).

Can it handle all the above inputs effectively?
Would you recommend it for use in an RV?
Any thoughts on the impedence issue (I don't have the Kenwood model number, but it is the radio the ground responders have in their vehicles).

For others that have used the GMA 340, it seems it has the capability to handle multiple inputs, per the spec sheet, and can handle the separate comms. Any feedback on the 340's abilities and performance would be greatly appreciated. Also, any positive or negative feedback on the 340's intercom capability would be welcome as well.

Thanks Much!
Bob

"Rocket" RV-6
N600SS
4SD

 

[rvmills]

Thanks Mark!

Mark,

Thanks for the great feedback. I have a spec sheet for the PM4000 in hand, and took a good look at your Tactical Radio Adapter and the PM8000B website info. Looks like either could be a great option. That 8000B sure looks like a very sweet setup, with all the features, the 4 unswitched inputs (like the 4000), and the external audio/phone jack! It's back to the panel planner for some tweaking, and to the "CFO" for some negotiations!

Quick follow-on question: In the case of the 4000 or the 8000, the Tactical Radio Adapter is required for either, but can be "buried" (requires no user interface once set up and connected). Correct?

I'll also double check with the member using the GMA 340, and see what he's using in his set up.

Thanks again for the detailed info...great to get such "straight from the source" information!

Cheers,
Bob

 

[mscheuer]

The Tactical Radio Adapter is mounted in the blind, once you set it up (there are dip switches and potentiometers) there is never a need to have to access it again.

I appreciate your consideration of our panels, we are all dedicatd to making the best audio sysgtems for GA, and we have lots of fun doing so as well!

Sincerely,
Mark Scheuer
PS Engineering

 

[rvmills]

Thanks again Mark! I also noted in shopping around that the price delta from the GMA 340 is down to about $200-220. Pretty darn good for the extra features (IntelliVOX, 4 unswitched audios, phone/ipod jack, etc!)

Turns out the local friend is using the 340 with the tactical radio (works with no adapter in his case), and it turns out that any of the three Comm inputs can handle it (you were correct, there is no difference between the three). I'd have to use the TRA, but I'm still leaning that way due to the quality of, and service behind, PS gear. Now just need to turn the paper panel mods into the real thing! Thanks much!

Bob

 

[mscheuer]

Bob, if your friend is using his tactical radio with the GMA340 without a Tactical Radio Adapter, and if you use the same tactical radio your friend has, then you will not need the Tactical Radio Adapter with the PMA8000B.

Good luck with your panel.

Mark Scheuer

 

[rvmills]

Bob, if your friend is using his tactical radio with the GMA340 without a Tactical Radio Adapter, and if you use the same tactical radio your friend has, then you will not need the Tactical Radio Adapter with the PMA8000B.

Good luck with your panel.

Mark Scheuer

Mark, that would be great...simplify the install, and make the choice easier!

Another member has a PM4000 and needed the TRA (he loves the 4000 in his Nanchang CJ...talk about a noisy environment!).

Are there electronic differences between the PM4000 and the PM8000 that might account for the 8000 not needing the TRA? I'll talk to the gent that did both installs tomorrow, get the Kenwood model, and bounce it off you...if this reveals another capability for the 8000, great news!

Thanks again!
Bob

PS: This kinda became a Tactical Radio Adapter thread, but what the heck!

 

[mscheuer]

Are there electronic differences between the PM4000 and the PM8000 that might account for the 8000 not needing the TRA? I'll talk to the gent that did both installs tomorrow, get the Kenwood model, and bounce it off you...if this reveals another capability for the 8000, great news!

Bob, I based my opinion that you would not need a TRA because the radio your friend installed (assuming it is the same as you have) didn't need one with the GMA340. The aircraft radio input circuitry is the same with both the GMA340 and the PMA8000B.

Hope this helps.

Mark

 

[rvmills]

Mark,

Talked to the other pilot and the installer today, and the Tactical Radio is the Kenwood TK-760. Turns out that it works with the GMA 340 (no TRA) at the expense of not having sidetone when transmitting on Comm 2 (which the other pilot doesn't mind, but I'm thinking I might not like).

In looking at the pilot guides for the 8000B and the 7000M-S, I see that when in split mode, you lose the ICS, but can regain it by selecting the ICS audio on (7000), or toggling the ICS to all or crew (8000B). Perhaps that would work when on Comm 2, and would at least give the apperance of sidetone via the ICS.

Is there a possibility of adding jumpers, etc. to overcome the loss of sidetone? Then again, maybe it'd just be best to not be a penny-pincher, and get the TRA, and keep it simple!

Thanks again for all the feedback, I've really enjoyed looking at and (trying to) get smart on your gear!

Best,
Bob

"Rocket" RV-6
N600SS
4SD

 

[mscheuer]

There is a sidetone mod, but....unfortunately, it is for all coms, not just for one. So, if you were to select the sidetone mod (removing a jumper on the Printed Circuit Board), then your aviation radio would have both its sidetone AND the phuesdo sidetone, and that leads to very bad sounding sidetone.

The copilot won't be able to hear your transmissions and if that is important, then you might consider the TRA. It would not be desirable to turn off your sidetone in your aircraft radio so you could enable our "sidetone generator" because sidetone from your radio also assures you are getting good audio to your aviation radio transmitter.

So, long story, no real good solution except for the TRA, but I bet your copilot could just left up one ear piece to hear what you are saying...just a suggestion!

It's been my pleasure talking with you, this is what we do so I always enjoy talking audio stuff.


Mark

 

[rvmills]

Thanks very much Mark. If you're at SnF, hope you are having a great time, and even more thanks for taking time out to reply. I'll follow your advice and leave the internal mods alone. Will give it a try without the TRA and add that if it becomes necessary. Great to know the option exists. Lynn at Aviation Classics says hello! He speaks very highly of your gear!

 

[mscheuer]

Yes, we are really enjoying Sun 'N Fun during our 23rd year of being an exhibitor. It is amazing how fast this time has past.

We have also had many RV visitors at our booth. The PMA9000EX is of particular interest for most of them.

Look forward to hearing of your results with the TR.

Take care.

Mark

Thanks very much Mark. If you're at SnF, hope you are having a great time, and even more thanks for taking time out to reply. I'll follow your advice and leave the internal mods alone. Will give it a try without the TRA and add that if it becomes necessary. Great to know the option exists. Lynn at Aviation Classics says hello! He speaks very highly of your gear!