|
Vintage Amateur and Military Radio Amateur/military receivers and transmitters, morse, and any other related vintage comms equipment. |
|
Thread Tools |
8th Feb 2017, 1:25 pm | #1 |
Dekatron
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
|
AN-5730-3 Transmitter What Aircraft?
I have a compass or direction indicator that states use only with above transmitter. It is American and I wonder what plane it would have been used on?
It seems the National Air and Space Museum have the same instrument but not much detail about it. Thank you.
__________________
G8JET BVWS Archivist and Member V.M.A.R.S |
8th Feb 2017, 3:23 pm | #2 |
Dekatron
Join Date: Aug 2003
Location: near Reading (and sometimes Torquay)
Posts: 3,086
|
Re: AN-5730-3 Transmitter What Aircraft?
It's not a RADIO transmitter!
The transmitter in question is just the thing that transmits the compass bearing to the indicator. Effectively it is the actual compass. As for what plane, I suspect loads of them. |
8th Feb 2017, 3:26 pm | #3 |
Nonode
Join Date: May 2007
Location: Preston, Lancashire, UK.
Posts: 2,510
|
Re: AN-5730-3 Transmitter What Aircraft?
A picture would be interesting, if possible please.
Many thanks, Andy |
8th Feb 2017, 3:27 pm | #4 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,953
|
Re: AN-5730-3 Transmitter What Aircraft?
Doesn't "AN" in a US equipment-designation mean "Army/Navy" ??
There again, that doesn't necessarily help: at one time military aviation came under the US Army - https://en.wikipedia.org/wiki/United...rmy_Air_Forces |
8th Feb 2017, 3:27 pm | #5 |
Moderator
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,801
|
Re: AN-5730-3 Transmitter What Aircraft?
Look up 'synchro transmitter' and you'll see a 3-phase electrical arrangement to transmit rotary position information. The compass is stuck somewhere convenient in the aircraft, and the display instruments (it can drive more than one) go in the panels for the pilots and navigator
David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done |
8th Feb 2017, 5:16 pm | #6 |
Dekatron
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
|
Re: AN-5730-3 Transmitter What Aircraft?
Thank you all.I will post a picture Andy.
__________________
G8JET BVWS Archivist and Member V.M.A.R.S |
8th Feb 2017, 5:48 pm | #7 |
Rest in Peace
Join Date: Jan 2015
Location: Cottesmore, East Midlands, UK.
Posts: 858
|
Re: AN-5730-3 Transmitter What Aircraft?
GMB has nailed it. The "Transmitter" in this case is a flux valve (or flux gate, if you're American), which is a magnetometer-type device used to sense the direction of the Earth's magnetic field relative to your aircraft. Its output is used to drive the aircrew's compass indicator.
It's generally mounted on a wingtip or at the top of the tail fin to get it as far away as possible from any iron or steel components on the aircraft which, being magnetic themselves, will affect its accuracy. The problem with flux gates is that they work best when they're orthogonal to the Earth's magnetic field, ie, when you're flying straight and level. The flux valve is usually mounted on a wee pendulum to allow the aircraft a certain amount of freedom in pitch and roll before it becomes inaccurate. Since aircraft, particularly military aircraft, can be chucked about all over the place, this type of sensor is pretty limited on its own. On the other hand, the rotor of a gyroscope bolted to the airframe will maintain its alignment relative to the surface of the earth, regardless of the aircraft's attitude, so if you tell the gyroscope where North is before taking off, you can use that as a compass (hence gyro-compass) The problem with gyroscopes is that they tend to drift and become inaccurate after a while. They get round this by slaving the gyroscope in yaw to agree with the output of the flux valve, so you get the short-term versatility and accuracy of the gyro, combined with the long term steadying influence of the flux gate: you can throw your aircraft around as much as you like, and the compass will still give you good short-term and long-term accuracy. As a bonus, you can also measure the pitch and roll angles of the gyro rotor with respect to the airframe, and use these measurements to drive your Artificial Horizon, and/or you can take all three outputs from the gyro - pitch, roll and yaw - plus the output from your altimeter, feed them to a computer (analogue or digital) and send them to your flight controls to form an Automatic Pilot. AS GMB stated, a gyro-compass is a fairly standard piece of kit and this could have been fitted to many types of aircraft. Coincidentally, there's a "Transmitter" for your indicator for sale on Ebay at the moment. Cheers, Frank Last edited by frankmcvey; 8th Feb 2017 at 6:00 pm. |
8th Feb 2017, 7:11 pm | #8 |
Dekatron
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
|
Re: AN-5730-3 Transmitter What Aircraft?
Great stuff Frank ,no I won't be buying anything to go with it. Do we have a year or roughly when it would have been used?
__________________
G8JET BVWS Archivist and Member V.M.A.R.S |
8th Feb 2017, 9:03 pm | #9 |
Rest in Peace
Join Date: Jan 2015
Location: Cottesmore, East Midlands, UK.
Posts: 858
|
Re: AN-5730-3 Transmitter What Aircraft?
There's a US patent for the flux valve dated 1941. However, there's a also a patent for gyro-magnetic compasses dating further back to 1938.
Most RAF WW2 aircraft used good ole magnets-in-oil compasses; I don't know what systems US aircraft used. Certainly, gyro-magnetic compasses were used on 1950s British military aircraft such as the Hunter and the Lightning. The Lightning flux valve was a bit smaller than the one shown on Ebay and had a dome-shaped enclosure for the pendulum, rather than the cylindrical one on Ebay. The Ebay item has a post war look. Apparently this particular system (the Bendix Pioneer compass) was fitted to the Piper PA-24-250 Comanche which was 1958. Cheers, Frank |
9th Feb 2017, 11:35 am | #10 |
Pentode
Join Date: Apr 2011
Location: Swansea, Wales, UK.
Posts: 143
|
Re: AN-5730-3 Transmitter What Aircraft?
Flux gate compasses are still used for the auto pilot and heading display on boats. In 1927 the Spirit of St Louis had an Earth Inductor Compass which used flux gate principles. I wonder if a replica will fly the Atlantic for the 90th anniversary.
73, Andrew |
9th Feb 2017, 11:44 am | #11 |
Dekatron
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
|
Re: AN-5730-3 Transmitter What Aircraft?
Pics enclosed.
__________________
G8JET BVWS Archivist and Member V.M.A.R.S |
9th Feb 2017, 2:37 pm | #12 |
Octode
Join Date: Jun 2013
Location: Huddersfield, West Yorkshire, UK.
Posts: 1,782
|
Re: AN-5730-3 Transmitter What Aircraft?
Hi Peeps.. In the late 60's I had an aerial rotator assy, which was cvalled the Number 1 Mechanical unit, which I was told came from Heavy bomber aircraft, possibly to rotate a DF aerial. It had a Display similar to the one posted by Hamish. The conical adaptor to fit to an antenna tube, were like the proverbial "rocking horse exhaust" I made mine with steel plate and a piece of scaffold tube welded to it. I wonder if any members remember this item......it was beautifully made internally, with two DC motors continually running, to a differential gear assy, and one motor was stopped the other rotated the shaft . The direction meter was connected via a four wire plessey plug.
__________________
Should get out more. Regards Wendy G8BZY |
9th Feb 2017, 2:47 pm | #13 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,953
|
Re: AN-5730-3 Transmitter What Aircraft?
I kind of know something similar to what you describe: I always believed they were propellor-pitch controllers!
|
9th Feb 2017, 2:48 pm | #14 |
Moderator
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,801
|
Re: AN-5730-3 Transmitter What Aircraft?
Do not open. Check for radioactivity before anything else.
Dumped refuse from WWII aviation instruments is the cause of the worst contamination in the UK (Google Dalgety Bay) David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done |
9th Feb 2017, 3:55 pm | #15 |
Octode
Join Date: Jun 2013
Location: Huddersfield, West Yorkshire, UK.
Posts: 1,782
|
Re: AN-5730-3 Transmitter What Aircraft?
Hi Tanuki....
I kind of know something similar to what you describe: I always believed they were propellor-pitch controllers! Its strange that... this was mentioned yesterday... maybe they were...but were sold as aerial rotators from NW Electrics in manchester.
__________________
Should get out more. Regards Wendy G8BZY |
9th Feb 2017, 4:20 pm | #16 |
Dekatron
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
|
Re: AN-5730-3 Transmitter What Aircraft?
This gets more intresting. Thank you all.
PS I will Not open it,funny I did wonder about radiation.
__________________
G8JET BVWS Archivist and Member V.M.A.R.S |
9th Feb 2017, 4:29 pm | #17 | |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,454
|
Re: AN-5730-3 Transmitter What Aircraft?
Quote:
Lawrence. |
|
9th Feb 2017, 6:54 pm | #18 |
Nonode
Join Date: May 2007
Location: Preston, Lancashire, UK.
Posts: 2,510
|
Re: AN-5730-3 Transmitter What Aircraft?
I remember visiting that shop sometime during their last years in the late 60's. When did they finally close? (sorry if this is going OT).
Andy |
9th Feb 2017, 7:18 pm | #19 |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
Posts: 13,454
|
Re: AN-5730-3 Transmitter What Aircraft?
I don't know when he closed Andy, I used to go there quite often in the 1960's, he used to run an ad in Shortwave Mag, back then there used to be a surplus place just round the corner on the right hand side of the beginning of Oldham Rd, New Cross Radio? there was Globe Radio which I think was on Shudehill, there was also a component shop near the top end of Tibb St, then there was Mazels down on London Rd.
EDIT: Forgot RSC in Brown St. Manchester just off Market St. Lawrence. Last edited by ms660; 9th Feb 2017 at 7:38 pm. |