Very helpful suggestions , all!!
Sent from my iPhone
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On Dec 20, 2017, at 07:48, Vince Vielhaber <vev@...> wrote:
Ok, replying to myself here. Like I said, I'm not convinced there's
anything wrong with the Si5351.
Is the raduino mounted in the case or is it out by itself? If it's
installed, remove it so we can eliminate the other variables.
1) double check that the 25MHz sketch from Gordon still works.
2) see if the 7075 sketch from Gordon works.
If it does...
3) load Farhan's sketch and see if that works.
NOTE: All of these tests the raduino is not mounted in the case and is not
connected to anything other than the computer that's loading the sketches.
4) if Farhan's sketch works, try loading Allard's sketch - the one you
originally tried using.
To determine the freq you should be hearing on your HF rig, take the freq
on the display and subtract it from 12.000. So if the display reads
7.3000, subtract that from 12.000 and you should hear something at or near
4.700 MHz. It probably won't be right on freq.
Vince.
After all of that we'll have a better view on where we stand and where to
go from there.
The part is Si5351. Yes you can replace just the chip, but you'll need to
be able to do surface mount ICs. You can get the chip from Digikey for
just under a buck. If you prefer Mouser, it's $1.15 ea. I just ordered a
bunch from Digikey.
I'm not convinced it's the chip but I haven't caught up on email yet so
I'll hold further comment for now.
Vince.
"It's a Yaesu FT-891. With the regular sketch, I looked for it from
4.8-5.5 mhz. With yours, I looked for it about 200 below and 500 above
7.025 mhz
Isn't the Si5351 just a chip? Can't I just replace the chip?"
?1. The sketch (I just sent it again to be safe) should force your
Si5355
to product a 4.925 Mhz Signal. So you would cozy the input coax center
conductor ofyour radio up to the raduino output wiring and hunt around
4.925 MHz. (When you add 4.925 + 7.075 MHz, you get 12.000 Mhz --- so
that is the reason this VFO setting shoulld tune the BITX receiver to
7.075 MHz---- but you will NOT hear any signal from the bitx at 7.075
Mhz.....
2. Si5151: I had to actually go hunt for it. I think it is a tiny
surface mount chip with 5 leads on each side, making a total of 10
leads,
soldered in.
Gordon
________________________________
From: [email protected] <[email protected]> on behalf of
tausciam@...
<tausciam@...>
Sent: Tuesday, December 19, 2017 11:47 PM
To: [email protected]
Subject: Re: [BITX20] Help! I think I may have just ruined my 9 year
old's
Chanukah
On Tue, Dec 19, 2017 at 08:38 pm, Gordon Gibby wrote:
?When you get the chance, can you give us more specifics on how you
connected your communications receiver, how you hunted for the signal?
On
what frequencies?
It's a Yaesu FT-891. With the regular sketch, I looked for it from
4.8-5.5
mhz. With yours, I looked for it about 200 below and 500 above 7.025 mhz
If it truly isn't there --- andyou CAN get the 25.0000 MHz signal
(still,
right?) then it is possible some portion of the Si5351 isn't working
properly. I'm not an expert onthat system of phase locked loops etc.
Isn't the Si5351 just a chip? Can't I just replace the chip?
--
Michigan VHF Corp.
--
Michigan VHF Corp.
