Microair experience

[pbugg]

I have Xair, fits same hole and works great. One small problem under warrantee and fixed double quick (and upgraded to latest board) at no charge. faultless performance, way better than my old Icom. New price very competitive. compare the market and make decision.

 

http://www.xcomavionics.com/comparison/comparison.html

 

 

[geoffreywh]

I like Microair. I had a problem with mine. They checked and upgraded my radio, sent it straight back. The problem turned out to be the antenna, They went way past normal service and were extremely helpful, can't have better than that.

 

 

[Peter Anson]

I have had a few "problems" with my Microair and they have always turned out to be connection faults. One was the connection to the antenna. Another was the mic on my headset and most recently a dodgy PTT switch ($1.75 from Jaycar). I originally bought it 2nd hand and when installing it thought it did have a fault (it didn't, I had made a mistake in the wiring). Microair checked it for me and posted it back when they said they would. The service at the time was pretty good. I guess that makes this one more plus vote.

 

Peter

 

 

[Blueadventures]

Today a friend showed me his microair 760 version N2 fault which when transmitting on 126.7 the headset get bad squelch type noise and is heard at 1 out of 5 and very unreadable.  On 123.45 on transmit no noise and is received at 3 out of 5. Any ideas if adjust mic gain or sidetone pots on side of radio need adjusting. Used both Bose and pilot brand head sets.

[FlyBoy1960]

if the noise varies depending on frequency then it is Antenna VSWR which is at fault. Probably drop an antenna analyzer into the system and get it to plot a graph. One of the guys at our airport as this fantastic one where you connect it up, press a button and it displays a graph of the aerial VSWR across the entire aviation frequency range, expensive bit of kit but it does the job in about 30 seconds

[Blueadventures]

19 minutes ago, FlyBoy1960 said:

if the noise varies depending on frequency then it is Antenna VSWR which is at fault. Probably drop an antenna analyzer into the system and get it to plot a graph. One of the guys at our airport as this fantastic one where you connect it up, press a button and it displays a graph of the aerial VSWR across the entire aviation frequency range, expensive bit of kit but it does the job in about 30 seconds

Thanks; what is the fix for that.  Redo the cable ends or replace with better grade of cable?  Thanks for info.

[FlyBoy1960]

You need to adjust the antenna length, check all the cable for the appropriate resistance to make sure it is not degraded by water all the fittings have not been crimped correctly but it is mainly due to the aerial length. Can you tell me what type of aerial is fitted to the aircraft, the ground plane and the type of coaxial used.

 

There are other experts here like Kyle who can give you much better information than I can

[Blueadventures]

Aircraft is a mates Skyranger. I’ll check through my images for the antenna and cable as aircraft is over an hour up the road. I was up there yesterday doings its first 25 hour service on its Rotax and repitch the prop. Tried two headsets same noise. Run out of time to look further for him or even adjust the sidetone or mic gain as he had to leave at 4pm. I passed on about the SWR and he will ask local lame at his airfield. Thanks and appreciate info. Mike

[kgwilson]

You will be able to get an antenna length chart for VHF on the web Then cut the antenna to the length in the middle of the frequencies you use most of the time. Measure from the ground plane to the tip. Worked for me.

[skippydiesel]

33 minutes ago, kgwilson said:

You will be able to get an antenna length chart for VHF on the web Then cut the antenna to the length in the middle of the frequencies you use most of the time. Measure from the ground plane to the tip. Worked for me.

SWR meter -  very handy for antenna tuning. Antenna length can be adjusted for your particular transceiver/antenna combination - no she'll -be -right -mate generalisation

[pmccarthy]

With my similar problem the SWR meter showed a soldering short in the antenna connector.

[Blueadventures]

The owner has another antenna on another aircraft, both are screw on to the base and he will change them out as next trial. Be nice if it’s the antenna for him. The rain is bucketing down and the highway is full of potholes so he cannot get to it today. Another mate lives next door to the airfield and he may have time get some images and change out the antennas and test at least a transmission on 126.7. If no feedback will be a positive. Thanks all for replies and I post the results, etc. Cheers.

[RFguy]

alright alright.

 

Did this radio and headset etc combination ever work, or is this a new install ????

 

or is this an previously working install, gone bad ?

 

UNless the antenna has a bit fallen off it is NOT going to be a VSWR problem due to a incorrectly cut antenna unless it is miles and miles off .  It will affect the radio performance a little , but unless it is a dead short, dead open or varies more than 30% from the right length, it wont matter.

 

Most problems I see are coax/connector issues, and power issues - HR joint...

You can diagnose 90% problems with an ohm meter looking for shorts from inner to outer of the coax plug (a BNC) , and checking for continuity from the shield (outer) to chassis/airframe  ground (should should occur at the antenna base) .   (fibreglass planes are a bit different) .  if HEARING a faint signal, grabbing the END of the antenna should make the faint signal weaker.  (the end of the antenna is sensitive to disturbance ) . 

 

BTW you can get yourself a super excellent graphing VSWR meter for about $200.  they are just as good as a $100,000 box for that job.

 

-glen-

 

 

Edited February 28, 2021 by RFguy

[Blueadventures]

21 minutes ago, RFguy said:

alright alright.

 

Did this radio and headset etc combination ever work, or is this a new install ????

 

or is this an previously working install, gone bad ?

 

UNless the antenna has a bit fallen off it is NOT going to be a VSWR problem due to a incorrectly cut antenna unless it is miles and miles off .  It will affect the radio performance a little , but unless it is a dead short, dead open or varies more than 30% from the right length, it wont matter.

 

Most problems I see are coax/connector issues, and power issues - HR joint...

You can diagnose 90% problems with an ohm meter looking for shorts from inner to outer of the coax plug (a BNC) , and checking for continuity from the shield (outer) to chassis/airframe  ground (should should occur at the antenna base) .   (fibreglass planes are a bit different) .  if HEARING a faint signal, grabbing the END of the antenna should make the faint signal weaker.  (the end of the antenna is sensitive to disturbance ) . 

 

BTW you can get yourself a super excellent graphing VSWR meter for about $200.  they are just as good as a $100,000 box for that job.

 

-glen-

 

 

Hi RF  Thanks for comments.  New install.  Aircraft has just 23 hours.  123.45 worked good at 3/5  but 126.7 US at quite 1 and gets feedback noise loud while transmit button pressed.  I read history of radio is that it was sent to Microair 2 years ago (March 2019)  bench test and minor repair, solder etc on mic 2  (cost about $460 all up; appraisal and then 3 hours repair / test at $140 / hr, :-) Always been noisy on transmit.  Passed on to try a proven antenna; he may buy a better type antenna, also trying to get some images of the existing one.  I would describe the antenna as being a f/g with wire on outside from memory under plastic.  Base is chromed brass or s/s and screws onto its mount.  Hopefully get some images of it today or tomorrow.  The fact is transmits ok on 123.45 and noise and poor transmission on 126.7 is interesting to me.  Tried Bose ANR (on and off) and a Pilot brand set all the same.  Cheers

 

What brand is the $200 ish SWR meter.  May need to get one; he is going to try and source some LAME help at the airfield as they may have a SWR meter there.  He is at Lakeside, also may look at an accompanied flight to Shute if there is a SWR there.

Edited February 28, 2021 by Blueadventures

[RFguy]

OK, so 123.34/126.7 isnt far enough  apart to really draw any conclusions.

  and also, you dont really know the performance of other aircraft that you communicate with so it is hard to draw any coclusions from that, either, given they their installas and antenna setups all vary alot.

 

the GROUND  return for the antenna could well be upsetting the radio.  that is a lack of good ground plane.  OK so it is a whip. whip should be cut 59cm from the bottom of the insulator bit to the tip) . The antenna really needs at least two, preferably four  wires each 60cm long going off in four different directions, roughly.  the more the better. (8 will be better than 4 on a plastic plane) .....

If it has a metal frame, the antenna base should be connected to it. 

 

To measure power and VSWR, a thru-line measurement, 

https://www.ebay.com.au/itm/VSWR-POWER-METER-AVAIR-AV-20-1-8-200MHz/184629802015?hash=item2afccb341f:g:JA0AAOSw6yBeWbPR

is a good one. you will need a couple of adaptors to get in and out of the PL-259 connectors

This is  a particular good meter for the money and very suitable .  you can meter power and VSWR simultaneously

also : cable PL259 (meter)  to BNC male  (radio) 

PL259 male to BNC male RG58A/U 50Ohm Coaxial Cable M type UHF Cable -Top Quality | eBay

 

that seller is OK. get 2m long.

 

the BNC socket to PL259 plug adaptor to accept the antenna :  you need : ONE of

 

PL259 UHF PLUG MALE TO BNC SOCKET FEMALE RF Adapter KP | eBay

or 

PL259 Plug to BNC Socket Adaptor | eBay

or

PL259 Male UHF PLUG to BNC Female Socket Adapter | eBay

 

all up you need to spend about $120. 

 

then , there are graphical swept meters. but for 99% of purposes you dont need swept. just trigger the meter at different frequencies to get the antenna VSWR at different parts of the band.... they dont need the radio , or a radio to work to use : 

This is an excellent unit- but cannot measure radio power.  can measure antennas of all types with airplanes (transponder antennas, VHF AM , HF , TV antennas, the lot.) 

 

Mini1300 4.3" LCD 0.1-1300MHz HF/VHF/UHF ANT SWR Antenna Analyzer Meter Tester | eBay

 

you'll need a BNC female (to accept the antenna)  to N male  (to analyser) to go with this.

#2 N Male to BNC female Converters Connectors Adapters | eBay

 

 

 

[Blueadventures]

5 minutes ago, RFguy said:

OK, so 123.34/126.7 isnt far enough  apart to really draw any conclusions.

  and also, you dont really know the performance of other aircraft that you communicate with so it is hard to draw any coclusions from that, either, given they their installas and antenna setups all vary alot.

 

the GROUND  return for the antenna could well be upsetting the radio.  that is a lack of good ground plane.  OK so it is a whip. whip should be cut 59cm from the bottom of the insulator bit to the tip) . The antenna really needs at least two, preferably four  wires each 60cm long going off in four different directions, roughly.  the more the better. (8 will be better than 4 on a plastic plane) .....

If it has a metal frame, the antenna base should be connected to it. 

 

To measure power and VSWR, a thru-line measurement, 

https://www.ebay.com.au/itm/VSWR-POWER-METER-AVAIR-AV-20-1-8-200MHz/184629802015?hash=item2afccb341f:g:JA0AAOSw6yBeWbPR

is a good one. you will need a couple of adaptors to get in and out of the PL-259 connectors

This is  a particular good meter for the money and very suitable .  you can meter power and VSWR simultaneously

also : cable PL259 (meter)  to BNC male  (radio) 

PL259 male to BNC male RG58A/U 50Ohm Coaxial Cable M type UHF Cable -Top Quality | eBay

 

that seller is OK. get 2m long.

 

the BNC socket to PL259 plug adaptor to accept the antenna :  you need : ONE of

 

PL259 UHF PLUG MALE TO BNC SOCKET FEMALE RF Adapter KP | eBay

or 

PL259 Plug to BNC Socket Adaptor | eBay

or

PL259 Male UHF PLUG to BNC Female Socket Adapter | eBay

 

all up you need to spend about $120. 

 

then , there are graphical swept meters. but for 99% of purposes you dont need swept. just trigger the meter at different frequencies to get the antenna VSWR at different parts of the band.... they dont need the radio , or a radio to work to use : 

This is an excellent unit- but cannot measure radio power.  can measure antennas of all types with airplanes (transponder antennas, VHF AM , HF , TV antennas, the lot.) 

 

Mini1300 4.3" LCD 0.1-1300MHz HF/VHF/UHF ANT SWR Antenna Analyzer Meter Tester | eBay

 

you'll need a BNC female (to accept the antenna)  to N male  (to analyser) to go with this.

#2 N Male to BNC female Converters Connectors Adapters | eBay

 

 

 

Thanks RF will pass on, is the 59cm from tip to end of insulation of antenna. So if antenna unscrewed, tip to end of plastic, not including the chrome end base that screws onto the mount. Appreciate your time and comments. Cheers.

[RFguy]

it's not too critical. Important to know that on most antenna bases, the antenna (brass stud)  starts from the bottom of the base (the 5/16 thread runs up from the base of inside the plastic and forms part of the antenna. In many cases, the screw on female will shroud  the thread. 

+/- 1.5cm isnt going to kill it. 

Edited February 28, 2021 by RFguy

[Blueadventures]

Got some images of the antenna, not good focus though.  Will get a ground plane fitted inside.  Also is the ground plane I put in my Nynja build in 0.5mm aluminium.

 

Edited February 28, 2021 by Blueadventures
add image and words.

[RFguy]

OK metal frame. and antenna Z bracket  attached to metal frame.

that is fine. no need for extra ground plane. just yet. .. and are those frame joints all welded, bolted, screwed / riveted / insulated ???

 

just make sure there is ,  with plug disconnected from the radio : , you will need an ohm meter . (multimeter) 

 

1) continuity between the outer of the plug  and chassis ground- IE verify that the antenna bracket is actually connected to the frame, and that the coax outer is also connected. anodized tube is an insulator ! you might need to scratch away some anodizing.

 

2) open circuit between inner and output of the plug (no short)

 

3) continuity between the inner of the plug, and the antenna base stud. might need a long bit of any wire to help the meter probes get to both ends...

 

that's really all that can go wrong there.

maybe sure the centre pin of the BNC is not too recessed, usually about 1mm behind the bayonet flange

 

-glen

 

 

Edited February 28, 2021 by RFguy

[Blueadventures]

The antenna is a whip at 56cm.  He did not do any ohms checks and now plans to got a new antenna.  I see the micro air one is 87cm so I texted him to phone them and discus what they recommend.  When I go up to fit the new on and replace the coaxial cable I do the ohms checks. Won’t be this weekend. I post the outcome.

 

[Blueadventures]

My friend still has issues with poor radio transmissions. He has a spare micro air so may change radios next. Regarding the plastic screw driver needed to adjust the sidetone etc could it be a fine jewellers type with shrink wrap on the shaft and handle or does it need to be totally plastic?

[Kyle Communications]

On 28/02/2021 at 9:01 AM, Blueadventures said:

Thanks; what is the fix for that.  Redo the cable ends or replace with better grade of cable?  Thanks for info.

Hahahah buy another radio...waste of money continuing try to fix a bad design

 

[Blueadventures]

7 minutes ago, Kyle Communications said:

Hahahah buy another radio...waste of money continuing try to fix a bad design

 

Agree, he has another microair, just needs to change it out and see what he has. Good or the same bad radio quality. He’s lucky in a way to have another.  He needs radio at serviceable level so he can visit places.  As it’s good on 123.45 and no existent on 126.7 seemed like a radio issue to my limited, almost nonexistent radio knowledge. Cheers.

Edited April 18, 2021 by Blueadventures

[Kyle Communications]

The VCO maybe dropping out....its a common issue with the Microair

 

[Blueadventures]

VCO?