skyview dirty rf ...testing... resolved.

[pbennett]

Re: skyview dirty rf ...testing...

Further to my post of 5 May, I installed my replacement SV-700 today and checked for radio interference. Resuts are interesting.
The Apollo GX65 could barely detect the difference between SV on and off. Same for the handheld Icom provided it was more than a foot from the SV. The MGL V10 was an entirely different proposition. The SV significantly masked weak signals with hash. Moving the V10 antenna had no effect.
Possibilities are:-
The SV does not radiate significant RF but may conduct it via the harness.
The GX65 may have superior filtering to the V10's.
Loom routing may be relevant.
The GX65 antenna is on top of the fus. The V10 antenna is on the bottom within a quarter wavelength of the concrete floor. The V10 signal may be much weaker on the ground but may be OK in the air.
I may have a mismatch between V10 and its antenna, reducing the signal.

Should be in the air next week to check how the V10 performs in the air. Regardless, I'm a candidate for the promised filter.

Peter

 

[schristo]

i picked up the dynon capacitive filters yesterday and tried them out in the plane... they work.  all three must be installed to gain benefit but there is now no difference in rf signal with the dynon on or off.

i have updated the original post with additional detail and a photo for reference.

 

[mmarien]

That's great news. How do we get the filters?

 

[dynonsupport]

We only started with two sets of filters that we gave to local testers. Now that we have positive feedback in both cases that the work, we'll have news shortly on how we will get the filters to all affected customers.

 

[rfazio1951]

I am running wires for the dynon network now, I'll be ordering the skyview soon. Just to be sure I understand the twisted pair wiring, the twisted pairs would be data1A & data 1B, then data 2A & data 2B? is this correct? Thanks.

 

[flybuddy]

We only started with two sets of filters that we gave to local testers. Now that we have positive feedback in both cases that the work, we'll have news shortly on how we will get the filters to all affected customers.

Can you post the part numbers for the filters from L-Com?

 

[dynonsupport]

We'll have these shortly (a week or two) for people experiencing the problem, but if you need a solution sooner:

L-com.com
DGFC9MF x2
DGFC37MF x1

monoprice.com
product ID: 4884

 

[pbennett]

Update on my post of May 7, I have now had two flights with the new panel. On my inbound call today, the tower had trouble with "background noise". I was using the Apollo radio, which is crystal clear on receive. My transmissions had been confirmed clear before the panel upgrade. Maybe it's not the Skyview, since I have a bunch of other stuff in the new panel, but I won't be doing more troubleshooting until I get those filters.

Peter

 

[dynonsupport]

Peter,
We have had zero reports of SkyView messing with outbound radio transmissions, and for that to be true, it would need to be a huge transmitter that would mess with all radios for miles around (like a stuck mic). The filters suppress RF only, and outbound transmissions aren't really affected by this. If your outbound transmission was affected by RF, your own 8W transmitter would cause a huge loop!

You're welcome to try them, but chances are very low they will have any affect on the issue you describe.

 

[pbennett]

Thanks DS. You are right where radiated RF is concerned. My setup seems OK in that regard. Some years ago I had to put bypass capacitors around the mic circuit of a headset to kill the "loop" you mention.
Conducted RF, which the filters would bypass, can't be ruled out though. I have installed the unused audio connection from the Skyview to the audio panel. If conducted RF were to interfere with the audio panel, it could cause the symptom. I'm not jumping to conclusions yet, but this is one of the easier possibilities to eliminate with the filters, which I need to make my MGL radio useable anyway.
And a thought - how would a Skyview user normally know if his transmissions were in fact noisier with the Skyview on? Noisy transmissions are so common they are seldom commented on, and I doubt anybody has tried controlled testing yet.

Peter

 

[mmarien]

Are the filters available yet ?

 

[flybuddy]

Are the filters available yet ?

They are backordered at L-Com...about 3 more weeks

 

[PhantomPholly]

Huh, just caught up with posts.

I can't help but notice that this "solution" looks very similar to another post where I recommended someone try a solution that worked for a competitor just to see if it helped, and was told by the Dynon folks that their stuff couldn't possibly be subject to those kind of RF problems.

I'm no EE like Brantel; just sayin'...



The original solution was from DigiKey.com, and although that was a 25 pin solution they also offer the correct ones if someone is in a hurry to get some.

 

[dynonsupport]

The other thread is about the D100/D180, and it does have the filters inside, just like that thread said. This thread is about SkyView. As we've said about SkyView, it does pass the EMI certification tests without additional filtering, but it appears some installs need an even higher level of suppression.

Also, the linked filters are D25's, of which the SkyView has none, so please do not run out and buy those filters.

 

[PhantomPholly]

Fixed my post to remove the reference to a specific (and in this case specifically wrong) solution.  Point being was to suggest a vendor with a solution not out of stock.

Sorry to hear that SkyView does not yet have the same level of filtering that my D180 has.  I admit it didn't occur to me that you would lower your engineering standards in the newer generation. Plastic planes seem to be a very harsh environment - I'm betting you'll modify newer ones based on this info.

 

[dynonsupport]

Now that makes it sound like we made a conscious decision to lower our engineering or testing standards to get SkyView to market, or something like that.

Let's be clear here - we did not lower our standards. The standard was always "meet or exceed RTCA DO-160F, category H, for aviation COMM, NAV, and GPS bands", and both products do that. Yes, the D100 series passed by a wider margin, but we did test SkyView with numerous customers before release and did not come across this issue. Now that we have a wider deployment of the product, we're learning that some customers' installations need more filtering than the standard requires, and we're working to provide a solution to affected customers.

 

[DjAg5dosk2]

Quick data point. My F1 originally equipped with BMA E1 Gen 2 gold box had severe RF. BMA always blamed it on poor wiring practice by the customer. I had all the bandaid solutions, no effect.

When I first powered up Skyview, I heard a "buzzing," it only manifests when unit is first powered up and my ships backup battery (not Dynon's) is powering the diode protected avionics bus.

It is TOTALLY silent after 1 minute and performs well. It is crystal clear in all areas of TX and RX. The filters are not needed. It is an outstanding unit in RF performance compared to BMA. Not to shabby in other areas either.

Best
Howard

 

[thibault]

L-Comm now says 2-days availability on the DB-37s and in-stock on the DB-9s.

Does that mean maybe a little earlier than we thought?

Thanks,

Tom

 

[mmarien]

How do we get the filters?

 

[thibault]

Support,

L-Comm now says in-stock on the DB-37s and the DB-9s.

Any idea on when they will get in our hands?

Thanks,

Tom Thibault