[GreenKeys] interesting ebay item, fsk modem?

Thu, 06 Mar 2003 09:43:27 -0800

Greenkeyers -

  These are Frederick 1280A units.  They are real slick TUs, but the
seller is not specific about two items...

1.  The standard 1280A has only RS-232 & MIL-188 interfaces.  Frederick
offers a current loop interface as an add-on option, but none of the pix
or text mentions this option.

2.  The 1280 & 1280A will indeed do diversity reception -  there are
separate PC boards for FSK transmit & FSK receive.  A 1280A can be
loaded with two transmit cards or two receive cards, or one transmit &
one receive card.
  There are two 1280A units in the auction, but none of the text or pix
mention which boards are present in the units.
  The best situation would be if those two units include two transmit
cards and two receive cards.  You can mix & match the cards as you
desire -  with the 2TX & 2RX cards you could make two transceive units.

  The 1280 & 1280A units can be controlled from the front panel, or via
an RS-232 link.  The receive boards use commutative filters.  The
displays are not LED, but a gas plasma panel -  the power supply for
this plasma display is a high-mortality item.
  The "CH" number in the display indicates which board (CHannel) the
front panel is controlling.  For each of the two CHannels, either the
"MOD" or the "DEMOD" annunciator will light up, indicating whether the
selected CHannel is a transmitter or a receiver.

73
Dave Ross    N7EPI    [email protected]

[email protected] wrote:
> 
> I am told by the seller that it will do loop/rs232 and some other stuff!
> 
> > Output is RS232 or Mil-188c or Loop if desired,external power supply
> > required max loop current 80ma. and 350 max 350 volts arc.
> > rttyman
> 
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3010921877
> 
> What do ya make of that?
> Looks kinda neat with the LED frequency displays (supersize the pictureS)
>