Transponder Goes Up To 8

I find myself holding a 747 transponder control head that I bought on
eBay as a toy for the kids. But, with echos of Spinal Tap's guitarist
in my head, I notice that the selector knobs allow the digits 0 thru 8
to be selected. What gives?

Actually 0-7. Three bit octal. All transponder codes are four digits - each
digit is 0-7. Technology comes VERY slowly to aviation.


"Mike Granby" wrote in message
...

I find myself holding a 747 transponder control head that I bought on
eBay as a toy for the kids. But, with echos of Spinal Tap's guitarist
in my head, I notice that the selector knobs allow the digits 0 thru 8
to be selected. What gives?

pgbnh wrote:
Actually 0-7. Three bit octal. All transponder codes are four digits - each
digit is 0-7. Technology comes VERY slowly to aviation.


"Mike Granby" wrote in message
...
I find myself holding a 747 transponder control head that I bought on
eBay as a toy for the kids. But, with echos of Spinal Tap's guitarist
in my head, I notice that the selector knobs allow the digits 0 thru 8
to be selected. What gives?




I think that is Mike's point. He is holding one that goes 0-8.

Mike Granby wrote:
I find myself holding a 747 transponder control head that I bought on
eBay as a toy for the kids. But, with echos of Spinal Tap's guitarist
in my head, I notice that the selector knobs allow the digits 0 thru 8
to be selected. What gives?

Just curious - but does it look like either of these:
http://www.angelfire.com/il2/aphs/txp2.jpg
http://www.angelfire.com/il2/aphs/txp.jpg

Or is it a LED display?

On Dec 19, 8:51 pm, Mike Granby wrote:
I find myself holding a 747 transponder control head that I bought on
eBay as a toy for the kids. But, with echos of Spinal Tap's guitarist
in my head, I notice that the selector knobs allow the digits 0 thru 8
to be selected. What gives?

Yeah, they frequently do on large airplanes for some reason. Don´t
know why, we never use ém


Bertie

On Wed, 19 Dec 2007 11:51:33 -0800 (PST), Mike Granby
wrote in
:


I find myself holding a 747 transponder control head that I bought on
eBay as a toy for the kids. But, with echos of Spinal Tap's guitarist
in my head, I notice that the selector knobs allow the digits 0 thru 8
to be selected. What gives?

Decade electrical switches are easier/cheaper to procure than octal
switches?

That's nothing, here (at 5:50 minutes into the segment)
http://media.pbs.org/ramgen/newshour...219_skies28.rm
you can listen to Mr. Michael Goldfarb, former FAA Chief of Staff
under Bush Senior, referring to Runway 41 Left! I believe he may have
meant runway 4L, as any airman knows there can be no runway numbered
higher than 36.

News Hour with Jim Lehrer:
Easing Airline Delays
The Bush administration unveiled new plans Wednesday to reduce air
travel congestion for the holiday season and beyond. Airline
regulation experts examine the plan.

Larry Dighera wrote in
:

On Wed, 19 Dec 2007 11:51:33 -0800 (PST), Mike Granby
wrote in
:


I find myself holding a 747 transponder control head that I bought on
eBay as a toy for the kids. But, with echos of Spinal Tap's guitarist
in my head, I notice that the selector knobs allow the digits 0 thru 8
to be selected. What gives?

Decade electrical switches are easier/cheaper to procure than octal
switches?

Wouldn't a Decimal switch go 0-9?

On 20 Dec 2007 12:41:47 GMT, Judah wrote in
:

Larry Dighera wrote in
:

On Wed, 19 Dec 2007 11:51:33 -0800 (PST), Mike Granby
wrote in
:


I find myself holding a 747 transponder control head that I bought on
eBay as a toy for the kids. But, with echos of Spinal Tap's guitarist
in my head, I notice that the selector knobs allow the digits 0 thru 8
to be selected. What gives?

Decade electrical switches are easier/cheaper to procure than octal
switches?

Wouldn't a Decimal switch go 0-9?

Umm... Good point. Oh well....

Perhaps the new New York Airspace Czar has the answer. :-)

On Dec 19, 6:06 pm, Jim Logajan wrote:

Just curious - but does it look like either of these:

http://www.angelfire.com/il2/aphs/txp2.jpg
http://www.angelfire.com/il2/aphs/txp.jpg

Similar to botrh, but identical to neither.

Here's the eBay link...

http://cgi.ebay.com/ebaymotors/ws/eB...m=230199151135

On Dec 20, 3:31 am, Larry Dighera wrote:

Decade electrical switches are easier/
cheaper to procure than octal switches?

That would explain 0-9, but these are 0-8.