I too have built a standalone 472 100 Watt TX with a PIC (and an AD9850).
The software I have written so far now handles CW, QRSS, DFCW and WSPR-2 and
WSPR-15 (thanks to Andy who wrote up a nice description of the WSPR
protocol).
Even with a simple ‘air cooled’ 10 MHz crystal (40 MHz with 4x PLL)
running the PIC timekeeping is quite good, and it seems good enough to have
the PIC running for more than a day and still getting WSPR decodes. If I run
it from a 12.8 TXCO it will be even better.
I now sync the TX (for WSPR) by getting the PIC out of reset exactly on an
even minute….
I am not sure if I am going to implement Opera. There is too much obscurity
here for my liking. Apart from the difficulty of getting a good and complete
description of the protocol it’s the secrecy itself that has no place in
radio amateurism (at least that is how I think about the issue).
As for being a despicable appliance operator: notice the 4066? Here I can
attach a key..
The PIC board will disappear. Possibly I will add a PIC to the DDS board
(will have to reposition the 7805 for it to fit). Either that or I will add
a small board with the PIC and connectors for the LCD display, the RS232 for
a terminal and possibly a rotary encoder.
Add a 24V 150 Watt Meanwell switching PSU and it’s a neat little
self-contained package.
See attachments for a photo of the current setup and a quicly drawn
schematic
73's Minto pa3bca
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Ceterum censeo Carthaginem delendam esse
-----Original Message-----
From: g3zjo
Sent: Saturday, February 09, 2013 20:43
To: [email protected]
Subject: Re: LF: Fwd: WSPR Test
Yes I know it is always nice to see home brew, even from despicable
appliance operators.:-)
Some recycling of some of my 500KHz rock bound modules.
Eddie
On 09/02/2013 19:22, Stefan Schäfer wrote:
Am 09.02.2013 19:58, schrieb g3zjo:
No time reference just very accurate PIC timing which is good for weeks.
Ah yes. BTW when using e.g. a netbook in /p WSPR tests it is totally
sufficient to sync the PC clock manually to your wrist watch (which
was synced at home), if necessary. So it is not really a pro-argument
for Opera that no timing is required. I've recently tested that at
home with my own transmissions...
PA, yes tiny by your standards, but it is the PA that has been
growing recently.
:-)
Pictures please!
Oh dear do you really like rats nests?
...and dirty fingers, yes ;-)
73, Stefan
Eddie
DSCN0476.jpg
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472KHz100WTX_Pa3bca.png
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