[amsat-bb] Re: Flex-5000

Robert McGwier rwmcgwier at gmail.com
Fri Apr 6 12:19:08 PDT 2007

Edward Cole wrote:
> At 05:34 AM 4/6/2007, Bob McGwier wrote:
>> I am using DEMI and DB6NT.   I have never liked the internal one thought
>> KM0T swears by it.  The new radio will be able use any kind of
>> transverter,  simplex, duplex, etc. with control done by the radio.
>> Bob
>> N4HY
>> Steve Meuse wrote:
>>> Robert McGwier expunged (rwmcgwier at gmail.com):
>>>> An announcement of a new radio was made by Flex Radio today.  It is a
>>>> completely full duplex radio.  With transverter, it will be a wonderful
>>>> satellite radio.  No sound cards, etc. will be required.  Again,  it is
>>>> completely full duplex.
>> --
>> Robert W. McGwier, Ph.D.
>> Center for Communications Research
>> 805 Bunn Drive
>> Princeton, NJ 08540
>> (609)-924-4600
>> (sig required by employer)
> I had a look a the info on the Flex Radio website.  I'd be interested 
> in more information when its available: interior photos and block 
> diagram.  For satellite use, hopefully freq offset separation between 
> RX and TX LO's is possible.  If it is, then satellite tracking 
> software may be written for the radio.  Couple that with appropriate 
> xvtrs and this will make a great satellite radio.

Completely, totally separates in the same box.  It will share the same 
antenna or not.  It will use the 0 dBm port in simplex or duplex mode 
for transmit transverter. You can set up the transverter port to be full 
duplex and run the transmit and receive converters simultaneously 
through the separate IF's.  You should have heard me howl when this was 
messed up on the first alpha model.  ;-).

> I'm playing with the SDR-IQ joined to a DEMI 144/28 xvtr for 
> experimenting on eme with JT65.  Having the direct USB connection is 
> a great work around the slower sound-cards.  Assuming the 5000 does 
> the same to get 190-KHz span.

Firewire.  This allows ONE cable for control and isochronous sampling 
for the transmitter and the two receivers.  The IF is delivered 
isochronously to the operating system where the DSP does all demod,mod, 
and detection.  192 kHz is chosen because the radio uses standard sound 
card rates to get it into the operating system easily.

Firewire was designed for this kind of operation with isochronous 
sampling and asynchronous tranmission for control.  It works well enough 
to deliver QSK operation.

> For full use of Linrad, dual Rx channels are needed where the two Rx 
> are slaved to the same LO for preservation of phase.  I'm wondering 
> if this is possible with the new radio with the extra Rx?

ALL oscillators are derived from the same sources where they need to be. 
  You will be have all LO's be in phase.  I cannot wait to do 
polarization diversity at Al Katz house with this radio.

> 73,
> Ed - KL7UW
> ======================================
>   BP40IQ   50-MHz - 10-GHz   www.kl7uw.com
> 144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w
> DUBUS Magazine USA Rep dubususa at hotmail.com
> ====================================== 

AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL,
"Taking fun as simply fun and earnestness in earnest shows
how thoroughly thou none of the two discernest." - Piet Hine

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