RT-359A transponder question
Lars
RT-359A transponder? We just got an altitude encoder to go with the
unit (an ACK A-30) in hope for a little better reception from the ATC
when flying in controlled airspace...
The ACK installation manual is fine, giving the pin numbers to connect,
but I don't have the RT-359A manual so I don't know which pin is which.
The connector on the back side of the RT-359A is two staggerd rows of
flat pins, the top one with 12 pins and the bottom one with 11 pins.
There is also two round alignment pins, one on each side of the bottom
row. I haven't got the mounting bracket with the female connector out
yet, maybe the pin numbers are printed on that one, but it is in a
rather awquard place so I don't want to start ripping things apart
until i know how to finish the job.
BTW, the X-ponder is in a Jodel D119, SE-XED.
cha...@uthscsa.edu
#s 2 to 22 right to left.
PIN
3 Remote IDENT Sw
5 Remote IDENT Sw
9 Switched A+ OUT (+LV)
2 GND
11 MODE C COMMON
14 A1
13 A2
15 A4
19 B1
17 B2
16 B4
21 C1
18 C2
20 C4
10 D4
22 A+ INPUT
12 LIGHTING
1 GND
23 PWR JUMPER
8 PWR JUMPER
For 14 VDC operation, connect pins 8 and 23. For 28 VDC operation,
connect dropping resistor between pins 8 and 23. Hope this helps,
Steve
Lars
Wonder if I dare power the encoder from the "Switched A+ OUT" pin. The
ACK manual recomends powering the encoder directly from the mains bus,
but that would require that we pull the fuse/circuit breaker before
startup or install a separate breaker for the encoder. Wonder why they
don´t recommend using the switched output? It´s only a 60mA current
draw, but maybe it is the 420mA warm up current that is the problem...
/Lars
cha...@uthscsa.edu skrev:
Rob Turk
"Lars" <lar...@gmail.com> wrote in message
news:1158227475....@i3g2000cwc.googlegroups.com...
>Wonder why they don愒 recommend using the switched output? It愀 only a 60mA
> draw, but maybe it is the 420mA warm up current that is the problem...
>
> /Lars
Probably to make sure that the circuitry has warmed up and stabilised enough
by the time you switch on your transponder. I have not checked the ACK A-30
specs but it usually takes a few seconds after power-up for the circuit to
give accurate readings.
Rob
Lars
I finally got the back end connector out, but was puzzled to find a
wiring slightly different from the one indicated above. Pin 8 and pin
22 seemed to be switched, the A+ input was to pin 8 and the jumper was
between pins 22 and 23. Can this be correct? The transponder has worked
fine as far as I can tell so I am reluctant to change anything... If
only I had the manual!
/Lars
cha...@uthscsa.edu skrev:
John_F
Your wiring will work fine. It just feeds the power switch in the
reverse direction but since it is just a switch it don't care which
way the current is through it.
Internally pins 8 & 9 tie togeather and go to the power switch "side
A"; pin 22 goes to the other side of the switch "side B". Pin 23 is
the true power input to the fuse and internal voltage regulator after
it goes to through the switch
John.
Lars
I was away from this group for some time and didn't see John_F´s
answer until today. I have had quite a bit of worries since it turned
out that the contact elements where missing in all but the used
positions, so we had to get new ones (at 10 bucks APEICE!). Now I'm
only waiting to lay my hands on a proper crimping tool to attach them
to the wires.
Anyway, it seems the wiereing was all wrong in the original
installation, where the power was fed to pin 8, and pin 22 and 23 was
tied together. I guess the Xponder would still operate under these
conditions (it has in fact done so for the last 20-odd years), but it
seems the power filtering and fuse section has been bypassed. Maybe not
so good... Wonder if I dare switch it back to the supposedley correct
wiring? Or maybe there is some quirq with our dear old box that
requires the filters to be bypassed?
/Lars