skippydiesel

2 hours ago, facthunter said:

Hoses that have a lowered pressure (suction) need a brass spring wound through their interior to stop them collapsing and blocking the flow, Nev

In the past, I would have agreed with you but it would seem that this is now not always necessary.

It may have something to do with most automotive cooling systems (including Rotax 9 range) having an expansion fluid recovery reservoir.

My hypothalamus is that, instead of the system going to  a high negative pressure when cooled (common in the old style cooling systems), it draws back the surplus coolant from the reservoir. If anything a small positive pressure results - hence the spurt of coolant when you open the cap after the engine cools to ambient.

My 912 has Gates Holden Gemini non reinforced automotive hoses on the radiator top/bottom. They are light weight (thin walled) very flexible and so far (5+ 5  years) no sign of collapse.

Mobile 1 have an informative page: https://www.mobileone.com.au/electro_acoustics/mic_main.html

I wonder - does coughing up the extra $$$ for silicon hoses not come with a potential negative - that being, the temptation not to do, in part at least,  your 5 year rubber replacement .

I make a point, at this time, of doing additional cooling system maintenance & inspection, such as coolant flush & replacement, blow any foreign bodies out of the out the radiator, check  coolant pump leak, inspection of all metal spigots for corrosion,metal fatigue, etc etc. Over the years I have found shaped automotive cooling hoses that fit my application almost perfectly. They are relativly light weight and cheap - not sure that I could justify the expense of silicon.

I appreciate that in the gyro world there are long distances between engine & radiator and finding suitable hose may be difficult  however I am sure that the Gates catalogue shows long hoses without ribs (the ribbed stuff is heavy & stiff).

This is what i fitted to my home made/modified Peltor ear muff/head set - works a treat. My mic has Pilot PA-5 only on it dont know what the X is for

Sooooo Glen - sounds like the electret is the way to go ?

I find it a little odd that the same headset can be purchased with either an electret or dynamic mic. Sometimes the only apparent visual change,is that one comes in/with a wire boom and the other a flexi boom.

ELECTRET V DYNAMIC microphones in aircraft heads set applications

Your advice regrading the PRO's V CON'S will be gratefully received

YEEEEHA!!!!! well done. Persistence and a little help from your friends - great!🙃

Word of caution: sounds like you may have increased the number of "mechanical" connections (bullet connectors) - it is always better to minimise mechanical connections as these reprise a potential failure or raised resistance point .

Photo of home home conversion of  Peltor ear muffs I had lying around mated with ex military tank head set

The zip ties arenot for securing the hose to the manifold(s) they are for holding them in position against the frame etc.

57 minutes ago, RFguy said:

I would never use zip ties in this application. At least no longer than an emergency temporary when you are out in the Tanami Desert. Like 30 days maximum.

AND

 

if you do use black zip ties, make sure you buy the ones with the METAL TONGUE. 

 

I would suggest NOT use the types with the plastic tongue, about 1 in 10 has a defect in my experience.

 

-glen

RF you must be purchasing from some cut rate store/brand. In all the many many years I have been using zip /cable ties I could count on one hand the defective ones. Not only is a defect uncommon, it is easy to ID the ones that dont work properly and replace with one that does.

Ground plane - My antenna is located under the rear fuselage.  Due to structural & space limitations, Longitudinally, I used a piece of flat aluminium strap, cant remember exactly how long, about 1.5 m X a bit wider than the base of the antenna and the minimal thickness from local metal merchant probably 1.5 mm. Drilled the necessary holes for securing screws and cable connection. - Horizontally, I used builders aluminium flashing which I molded and glued (silastic) to the curved sides of the rear fuselage, as far as I could go. Placed  a flat piece of aluminium (cut off the strap) on top to make a sandwich. System works better than expected - great reception/ transmission. Have been using this for the last 5 years or so.

There cant be that much to it - I have built a  well functioning, simple headset out of a Peltor industrial ear muff, parts from an old military tank headset and off the shelf parts. It doesnt have a volume control on the ear cup so the radio volume does that. The system works just fine including the microphone - will have a look for it (amongst all my junk) take a photo and post it..

Persistence pays - almost anyone who has the passion can & will learn to fly - do not be put off.

3 hours ago, M61A1 said:

We use them at work. I would rather a set of DCs any day. I have a small head and find the Peltors uncomfortably small, as in little to no undercut for your ears. Noise attenuation is average and comms barely acceptable.

What work ?? - steering an aircraft??.

Fair comment ,-for the ear muff part, I guess it all comes down to the shape of ones head and ears as for the comms - a mic is a mic is a mic - the only choice is dynamic or electret- comparability with radio?

I have no real grasp of the PROS V CONS of electret V dynamic - do you??

8 hours ago, Blueadventures said:

Thanks, not looking at then just curious of their price. Just thought you may have known their rrp.  What did the pre owned set cost you? Cheers.

$550-650 for the Rojone and $150 for the second hand Peltor 8003's. I expect to replace the ear cup cushion/seals on the Peltors so a plus $ there.

16 minutes ago, Blueadventures said:

Hi Skippy don’t hold out on the price telling that’s what this forums about; sharing info.  It’s good info as people are always comparing brands, quality and price.  It’s good to know how long the wiring insulation lasts as some sets don’t hold up in our environment.  It’s a pain when it cracks off.  Some sets last about 8 years same with ear cushions.

I’m planing doing an upgrade to two Sony units with the retro fit anr setup mentioned in another thread mid next year.

H Blue,

Easy for you to get the price, just contact  Rojone Pty Ltd sales.

If you check out their web site you will find they are offering quite a few spares, including ear cup foam cushion kits, mic wind socks, etc

Found a preloved Peltor 8003 - reasonable price - will give it a go and see if my memory of the product is accurate.

Fairly sure that when I Googled this, JayCar heat sink past was one of the many suggestions

Probably not polite to discuss cost on this Forum but these headsets seem to be very competitively priced.

Anyone know what he PROS/CONS of electret v dynamic microphones ???

I am pretty sure you can get it through Bert Flood but just try Google and you will find lots of options , especially on the Rotax Forum and other web sites where Rotax engines are discussed at length

5 hours ago, danny_galaga said:

There are a number of competitors to the Rotax 912 now. Jabiru and a Belgian company (name escapes me) to name two. Therefore there is competition and therefore pressure on Rotax to keep their pencil sharp. Buy whichever motor takes your fancy.

Don't want to get /start a debate - but as I said no real competition 😊

Bit more info on the Rojone products;

All comply with SLC80 Rating 28 (Class 5) - I think this is possibly the highest  noise attenuation standard.  Fixed wing (shown below) & helicopter variants. There are options for dynamic or electret noise cancelling microphones. Wire or flexi mic booms as shown. There is only one "cup" mounted volume control.  Seem to have a very good supply of replacement parts such as ear cup cushions, foam & mic "windsocks" About 40- 100 gms heavier than the very similar Peltor products 

It would seem that 3M (Peltor's parent company)is no longer making aircraft headsets - or at least not for sale in Australia. 

There is an Australian company making headsets using Peltor industrial earmuffs as the base, adding mic & boom , speaker volume and Y cable.

Their extensive product range looks good but other than making something similar myself (which works) I have no actual experience. 

Company name is Rojone

Contact:

Address: 44 Aero Road, Ingleburn NSW 2565
Sydney  AUSTRALIA

Postal Address: PO Box 1, Casula Mall NSW
2170  AUSTRALIA

Telephone: (+61) 02 9829 1555

Facsimile: (+61) 02 9605 8812

Email: [email protected]

Inox is good have a bottle of that as well as the WD liquids/spray can. I tend to use them for different things. The Inox is more expensive so am more careful with how much & what I use it on. The WD liquid gets used a lot, particularly for cleaning. The WD spray can,  infrequent use, mostly when I need a "jet" of stuff.

Non scientific observation: I find the WD -40 spray can fluid to be somewhat less persistent and viscus's than the liquid variant. I have both on the shelf but use the spray can  much less frequently.