Microair 760 probs

[Russ]

Erratic annoying gremlins pop up.

 

Squelch control fails

 

Outgoing transmissions cut off

 

Poor reception of me by others

 

These just crop up out of the blue, so........refurbish or replace.

 

 

[frank marriott]

Russ

 

Have you checked your battery voltage whilst transmitting?

 

 

[Guest Andys@coffs]

Lets take them 1 at a time

 

1) Squelch control fails.........What exactly do you mean....Do you mean that squelch works (no hiss) and that from time to time break through occurs where you hear hiss but don't necessarily hear any transmissions? or do you mean that you don't hear transmissions that you know have occurred........Squelch is an analogue control too far one way and you hear everything hiss related too far the otherway and you hear nothing... I would suggest that in the first instance until you get Rx and Tx working I wouldn't necessarily say anything about squelch....

 

2) Outgoing transmissions cut off....what do you mean, do you mean that mid Tx it goes back to receive, or that mid Tx the other party tells you they only hear 1/2 your transmission.....If the former could be as simple as a failing PTT switch/loom.... Suggest adding inline an SWR meter. that will tell you if the carrier is problematic and if the antenna matching to the Tx modules is Ok....but to interpret results requires radio knowledge....

 

3) Poor reception.......again what do you mean, poor audio over a strong carrier, or poor carrier so hard for others Rx squelch to activate...... We need more info to try and diagnose.

 

If you aren't radio aware get a radio guy to have a look, doesn't have to be airborne specialist any Ham radio guy or UHF supplier etc. should be able to fault find this.

 

Andy

 

 

[frank marriott]

Andy

 

I agree with where you are coming from. My suggestion re voltage was to maybe rule out an actual radio fault. As you would no doubt be aware the charging system on a J160 is almost nothing at idle.

 

On aircraft not flown regularly people tend to start, switch on radio/s, EFIS, strobe/s ,transponder etc. and taxi and then have broken Tx ( or no Tx) Often the battery is able to start the engine but runs down quickly under load without input charge. Has potential to change squelch voltage setting as well.

 

Sometimes, to a non radio type person (and I have no idea of Russ's background) something as simple as supply voltage check can save a lot of heartache chasing a fault that actually does not exist. I may well be off track in this particular case but worth mentioning.

 

The mod to series connection of the windings on the alternator does pick up charging volts to 14 @ less then 1000rpm but I have no info on the output at cruise power.

 

 

[Guest Andys@coffs]

Frank

 

Your suggestion is a reasonable one and I understand why you made it. My concern is that there is so little info in Russ's post that no one can do any analysis of what is happening to suggest places to look.

 

If as you suggest it is a battery then if voltage is decreasing to the point that Tx is impaired then I very much doubt the motor will start again without a top up...or if it does its going to be very sluggish in the start...if that's the case then new battery time...those odyssey battery's don't last forever....but for the cost in AuD you'd recon they should....someone somewhere in Au is making a killing! when you compare what yanks pay for the same thing

 

Andy

 

 

[frank marriott]

I am happy with the odyssey so far (forgetting about the price) I changed mine at 5years whilst it was still working fine but because of age I didn't want to run the risk of being let down whilst in the sticks.

 

Although a new car battery every couple of years is getting close as well.

 

 

[Russ]

Thanks guys......let me try to be clearer

 

On transmit.......button in, trans in progress, then all goes quiet but I,m still speaking, finger off button, then back on again, then again all is ok, I,m hearing my transmition.

 

Another craft calls back, that my general broadcast was very ordinary ( not same day )

 

Radio going great, then out of the blue background hissing etc increases, cranking up squelch reduces noise only, does not completely go. Later in flight I can reduce the setting to where it " usually" is.....should be.

 

Again........thanks