Jim
You make very good points as usual. The concept of internally mountable board is interesting. I did not think of that.
This is not a VGA typ HD DB-15. and I am not sure of the availability of std 15 pin cables. They were used extensively in early Ethernet connections. Officenet. I was just thinking simple and straight forward, either 4 female stereo jacks on the board or 1/8 mini cables octopus fashion.
I assume the '44 uses 15 pins because it has 8 audio channels to deal with (telling you right away that they're single ended <grin>). There ARE cables available for the DB15 that are straight through. (Game ports use them, for instance).
Just that twisted pairs (as in Cat 5 or phone wire) are so appealing for a balanced signal.
Will wait for others to weigh in. I just dont think we need all that mass, and we may be able to creep the design to make the box better.
Eric AA4SW
From: Jim Lux [mailto:[EMAIL PROTECTED]]
Sent: Friday, August 05, 2005 12:37 AM
To: ecellison; 'Don Newberry'; FlexRadio@flex-radio.biz
Subject: Re: [Flexradio] Delta 44 Breakout Box and Balanced audio
At 08:43 PM 8/4/2005, ecellison wrote:
Don
Yea!!! Thanks for the information! I have Tony KB9YIG awaiting a word to go ahead with 15 pin connector board kits to interface directly to the Delta 44 with 1/8 inch stereo cables or jacks. without external box etc. I have a mass of wires running all over the place with infernal ¼ inch connectors, and in the long term plans that just aint gonna cut it. ¼ inch is fine for guitars which dont go on DXpeditions, but there is a limit to 1930s audio connectors!
But those 1/8" connectors are also a pain. Why not make a 15 pin connector and cable that solders into the SDR1000 instead of the existing stereo 1/8" connectors?
BTW, HD15s (like those on the SDR1000 aux) are widely available, but the standard VGA extension cord is not a "all pins connected" kind of cable.
Most people will probably be putting the sdr stack into a box of some sort, so having soldered in pigtails to the boards isn't a crippling defect.
1/4" phone plugs may be a 1910 era technology, but at least they're big enough that intermittent connections and weak springs aren't a problem.
If I had to choose a cheap, PC board mountable, connector, I might go for a 8pin modular (i.e. like used for networks) or a minidin, with a distinct preference for the former (hey, it's got 4 twisted pairs... what more do you need for 2 I/Q sets)
I know you are making a different point here, however, would love it if you would consent to a drawing of the components you mention. Any ideas for filtering and isolation would also be appreciated. I think many folks will go the Delta 44 / 66? Route.
For anyone who is reading, Tony is also specing out a serial port to paddle circuit board with 1/8 stereo connection for CW which Ill produce and market.
Thanks
Eric
Spacecraft Radio Frequency Subsystems Group
Flight Communications Systems Section
Jet Propulsion Laboratory, Mail Stop 161-213
4800 Oak Grove Drive
Pasadena CA 91109
tel: (818)354-2075
fax: (818)393-6875
