Re: FS v4.0 SoftRock40 receiver
Hi Bob,
?
Yes, I mail a built/tested unit to you several days
ago.?
?
73,
Tony KB9YIG
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Friday, September 30, 2005 5:10
PM
Subject: Re: [softrock40] FS v4.0
SoftRock40 receiver
Tony
?
??? I sent you email the other day
for a sr40.I am not sure if you sent it out or not.I usually get a message
from you when you send out your mail.I havent heard from you and thought I
would jump in here before they are all gone.
?
??? ???
??? ??? ??? ???
??? ??? ??? ???
??? ??? ??? ???
??? ??? ??? 73 Bob ve3gkm@... ?
?
----- Original Message -----
Sent: Friday, September 30, 2005 4:02
PM
Subject: [softrock40] FS v4.0
SoftRock40 receiver
Good Afternoon All,
As I continue to build
SoftRock40 kits for various hams I now have ten extra built/tested v4.0
SoftRock40 receivers for sale at $38 each.? This price includes
mailing cost to your QTH.? Each receiver has been tested to make
sure the image null works properly and that the MDS is better than -130
dBm.? If you would like one of these receivers, send me an
e-mail.? If you are not satisfied with the receiver after you get
it, I will refund your money and pay the return postage costs.
Thanks
and 73, Tony KB9YIG
|
Re: FS v4.0 SoftRock40 receiver
Tony
?
??? I sent you email the other day
for a sr40.I am not sure if you sent it out or not.I usually get a message from
you when you send out your mail.I havent heard from you and thought I would jump
in here before they are all gone.
?
??? ???
??? ??? ??? ???
??? ??? ??? ???
??? ??? ??? ???
??? ??? ??? 73 Bob ve3gkm@... ?
?
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Friday, September 30, 2005 4:02
PM
Subject: [softrock40] FS v4.0 SoftRock40
receiver
Good Afternoon All,
As I continue to build
SoftRock40 kits for various hams I now have ten extra built/tested v4.0
SoftRock40 receivers for sale at $38 each.? This price includes
mailing cost to your QTH.? Each receiver has been tested to make sure
the image null works properly and that the MDS is better than -130
dBm.? If you would like one of these receivers, send me an
e-mail.? If you are not satisfied with the receiver after you get it,
I will refund your money and pay the return postage costs.
Thanks and
73, Tony
KB9YIG
|
FS v4.0 SoftRock40 receiver
Good Afternoon All,
As I continue to build SoftRock40 kits for various hams I now have ten extra built/tested v4.0 SoftRock40 receivers for sale at $38 each. This price includes mailing cost to your QTH. Each receiver has been tested to make sure the image null works properly and that the MDS is better than -130 dBm. If you would like one of these receivers, send me an e-mail. If you are not satisfied with the receiver after you get it, I will refund your money and pay the return postage costs.
Thanks and 73, Tony KB9YIG
|
Re: SSB demod, was Re: carrirer oscillator
On 9/30/05, Frank Brickle <ab2kt@...> wrote: --- In softrock40@..., Ramakrishnan Muthukrishnan These are somewhat independent issues. It is certainly true that the higher the sampling rate (~ADC freq) the more of the band you could see, potentially. However the output bandwidth of the QSD really depends on the specific components in the QSD. What it is in the case of the SoftRock I do not know.
One of the clever features of the QSD is that the effective Q of the sampling filters is constant over the tuning range of the QSD. Not something that affects the SR40 much, of course :-) Thanks a lot, Frank, for patiently explaining it. -- 73 - Ramakrishnan, VU3RDD
|
SR-40 changes for Kenwood IF 8.830MHz
I ordered a pair of crystals at three different frequencies close to the Kenwood IF. One set on the high side, two sets on the low side, inductors, and trimmer capacitors to see which one is the easiest to be able to park the SR-40 so I can look at +-10KHz on the Kenwood radio without getting signals close to the baseband.
When I get it figured out, I will let the list know which one worked the best, and we could then order a group buy.
I ordered the following crystals;
35.2512MHz, push this one 20.8KHz up, crystals are cheap, about $0.42 each 35.3037MHz, pull this one 28 KHz down, about $4 each 35.3280MHz, pull this one 56 KHz down, about $1.44 each
Stay tuned, same bat time, same bat channel, but hopefully a different bat frequency. Now where is that frequency counter?
Cecil Bayona KD5NWA www.qrpradio.com
'Never argue with an idiot. They drag you down to their level then beat you with experience.'
|
SSB demod, was Re: carrirer oscillator
--- In softrock40@..., Ramakrishnan Muthukrishnan <vu3rdd@g...> wrote: Is it correct to assume that "if there is no sound card, and if we have a higher sampling rate ADC, we can see more portion of the band"? Or rephrasing it this way - What would be the passband of the signal output from the QSD ? These are somewhat independent issues. It is certainly true that the higher the sampling rate (~ADC freq) the more of the band you could see, potentially. However the output bandwidth of the QSD really depends on the specific components in the QSD. What it is in the case of the SoftRock I do not know. One of the clever features of the QSD is that the effective Q of the sampling filters is constant over the tuning range of the QSD. Not something that affects the SR40 much, of course :-) 73 Frank AB2KT
|
Re: SSB demod, was Re: carrirer oscillator
On 9/30/05, Frank Brickle <ab2kt@...> wrote: --- In softrock40@..., Ramakrishnan Muthukrishnan
11025 * 2 = 22050. 22050 * 2 = 44100.
11025Hz is the center of the presumed "good" passband on typical soundcards capable of handling audio CD rates.
You don't want to downconvert to 0 because most soundcards have bandpass filtering that roll off towards 0 and the Nyquist frequency. If you downconverted to 0, you'd be filtering off most of the signal before it got to your signal processing.
Therefore you downconvert such that the signal of interest is in the "best" part of the soundcard passband. Thanks Frank. That's quite clear. Is it correct to assume that "if there is no sound card, and if we have a higher sampling rate ADC, we can see more portion of the band"? Or rephrasing it this way - What would be the passband of the signal output from the QSD ? -- 73 - Ramakrishnan, VU3RDD
|
Re: SSB demod, was Re: carrirer oscillator
But on the SR-40 the oscillator is fixed! if you want to listen to 7.058 you have 2KHz audio coming out, the only thing you can do is change the crystal (good luck) or use a DDS instead of the built in fixed crystal. If you want to listen to a signal on 7.0563, good luck! Now, if you are changing the crystal, try to get the frequency of interest away from 0 Hz. At 08:44 AM 9/30/2005, you wrote: --- In softrock40@..., Ramakrishnan Muthukrishnan <vu3rdd@g...> wrote:
I couldn't understand how the mixing down to the magic number 11250 is
obtained.. Would you mind explaining it a bit more? Sorry, typo. it's 11025. I got it right in a subsequent paragraph :-)
What I thought was that the signal at 7.056 gets downconverted to zero
IF and because of the soundcard sampling rate of 48 khz, we are able to tune +-24khz.. 11025 * 2 = 22050. 22050 * 2 = 44100.
11025Hz is the center of the presumed "good" passband on typical soundcards capable of handling audio CD rates.
You don't want to downconvert to 0 because most soundcards have bandpass filtering that roll off towards 0 and the Nyquist frequency. If you downconverted to 0, you'd be filtering off most of the signal before it got to your signal processing.
Therefore you downconvert such that the signal of interest is in the "best" part of the soundcard passband.
The subsequent mixing stage (complex oscillator at -11025 or whatever) then moves the signal down to 0 once it's in digital form. Then the remainder of the processing takes place.
73 Frank AB2KT
Yahoo! Groups Links
Cecil Bayona KD5NWA www.qrpradio.com 'Never argue with an idiot. They drag you down to their level then beat you with experience.'
|
SSB demod, was Re: carrirer oscillator
--- In softrock40@..., Ramakrishnan Muthukrishnan <vu3rdd@g...> wrote: I couldn't understand how the mixing down to the magic number 11250 is obtained.. Would you mind explaining it a bit more? Sorry, typo. it's 11025. I got it right in a subsequent paragraph :-) What I thought was that the signal at 7.056 gets downconverted to zero IF and because of the soundcard sampling rate of 48 khz, we are able to tune +-24khz.. 11025 * 2 = 22050. 22050 * 2 = 44100. 11025Hz is the center of the presumed "good" passband on typical soundcards capable of handling audio CD rates. You don't want to downconvert to 0 because most soundcards have bandpass filtering that roll off towards 0 and the Nyquist frequency. If you downconverted to 0, you'd be filtering off most of the signal before it got to your signal processing. Therefore you downconvert such that the signal of interest is in the "best" part of the soundcard passband. The subsequent mixing stage (complex oscillator at -11025 or whatever) then moves the signal down to 0 once it's in digital form. Then the remainder of the processing takes place. 73 Frank AB2KT
|
Stan, You might also want to check for cold solder joints in the oscillator circuit. I had the same symptoms and found a cold solder joint on the ground end of the 2.2K resistor off the emitter of Q2 (this is R5 in the schematic for the older version softrock40 that I built). You might try heating up some of those joints and making sure they flow nicely to see if that helps.
73, Kurt KC9FOL
Stan Rife wrote:
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Show quoted text
Thanks Mike. I have just finished double checking everything, physically. No problems found so far. I am not able to detect the oscillator at the crystal frequency. I think this, for whatever reason, may be the culprit. Still checking,
Stan Rife W5EWA Houston, TX K2 S/N 4216 -----Original Message----- *From:* softrock40@... [mailto:softrock40@...] *On Behalf Of *Mike WA8BXN *Sent:* Thursday, September 29, 2005 11:44 AM *To:* softrock40@... *Subject:* Re: [softrock40] Not working: HELP
Computers can be quirky! Try using the microphone input on your computer instead of the line input just be be sure thats not what its trying to get input from. If you have a scope, feed a signal into the sr40 in its tuning range and look at the audio output on the scope, you should see a nice sine wave. Or if you have no scope, if you have a signal source near the 7056 frequency, you can just feed the audio out into an audio amplifier, the sr40 is basically a wideband direct conversion receiver. If no output that way, try listening for the crystal oscillator on the sr40 with a receiver that tunes 10 meters. If you hear that ok, check carefully the windings on the toroid bot for good soldering and proper positioning. Oh, and you might try tracking down that problem of no green light on the one usb connection. It might be significant. It probably would not be a good idea to try to run the sr40 on 6 volts from a wall wart, unless its regulated it will probably be much more than 6 volts at the light load of the sr40, and even 6 volts probably is higher than the max voltage for the chips. Radio shack sells 7808 +5 V regulators for $1.59, that could be used with a wall wart to get the right voltage. Of if you have a self-powered (one that comes with a wall wart) usb hub, that could supply power for test purposes.
If you have an audio oscillator, you can try feeding that into the computer and you should see something on the powersdr display to check out the computer side of things.
Good luck and let us know what the problem was!
73 - Mike WA8BXN
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|
Very good Stan!!? Glad the little receiver is
working for you.
?
73,
Tony KB9YIG
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Thursday, September 29, 2005 5:37
PM
Subject: RE: [softrock40] Not working:
HELP
??? Finally got it.? NICE RECEIVER!!??
Went through touching up pins on the IC's and the filter again. Hooked it up
and VOILA !!
?
?
Stan Rife W5EWA Houston, TX K2 S/N
4216 ?
Hi Stan,
After building over forty of
the little SoftRock receivers I have seen what you are talking about
several times. With no signal at all getting through, it usually is
associated with the oscillator signal not being divided down to clock
the QSD quad switch.? Check carefully for open pins on the IC's and
solder bridges between IC pins.? Most of the time when a SoftRock
does not play right for me it is associated with a soldering
problem.
The usual things of making sure the right components are in
the right locations is fundamental.? Also check IC
orientation.? U1 for example has its pin 1 in the lower left corner
of the IC when the printing on the IC reads upright from left to
right.
One time with no signal getting thourgh I had a bad crystal
which may have gone bad by too much heat in soldering the grounding wire
to the crystal case.? Another time with no signal getting through
the coax connector on the end of the antenna coax had an internal
short.
On the plus side, all SoftRock40 units I have built have
worked properly, some with extra effort, with a baseline noise level of
about -137 dBm when the unit is calibrated for S9 (50 uV RMS) at -73
dBm.
I would be happy to chat on the phone with you if you would like
additional help.
73, Tony KB9YIG ----- Original Message
----- From: "Stan Rife" To:
Sent: Thursday, September 29, 2005
10:12 AM Subject: [softrock40] Not working: HELP
> I
finished the SoftRock last night and I plugged it in to one of my >
USB hubs...no green light from the LED. I put it back on the bench
and > verified everything and all looked ok. After messing with it for
a while > and > still not getting a green LED from my USB hub,
I decided to plug it in to > the USB on the back of the
computer...GREEN LIGHT. Wondering why the USB > hub > doesn't
put out 5 volts, but will worry about that later. I thought that >
the > 5 volts daisy chained from device to device. > So, it lit
up, but I am not receiving anything. The latest binary > was acting
really weird on my computer, so I reinstalled PowerSDR and then >
unzipped the binary's from August in to the SDR install. It appears to
> work > ok now, I think. I have no way of verifying that. All
I get is a little > background noise (I got this before though) and a
solid S-9 carrier at > 7.056, but this is ALL I ever got from the
software whenever I would start > it up with NO hardware. So, I hope
this is making sense, the SR-40 is > either > not working
properly, or the software is not working. > I can play the canned .wav
files and that works, but nothing from > the SR-40. Made sure my
LINE-IN port on the soundcard was selected, and > checked that the
volume was up sufficiently. I don't know what else to > check, or how
to check it. I am electronically challenged, sorry guys. >
Plus > it is hard to get back behind the PC to do anything. I don't
have a 5 volt > power supply. Can I use a 6 volt wall wart?? I didn't
see a 5 volt > regulator > on the SR-40. > Can someone
tell me where to start? And what about the S-9 carrier > at 7.056?? Is
that supposed to be there?? I do have an XG-1 signal source, > but I'm
not getting anything to the software. > >
Thanks, > > Stan Rife > W5EWA > Houston, TX >
K2 S/N 4216 > > > > > > > Yahoo!
Groups Links > > > > > > >
|
Re: SSB demod, was Re: carrirer oscillator
Agree. Why I talked about software is that the only way I can conclude the center frequency is 11.025khz is by looking at what the software is trying to do. I do not yet have SR40 hardware beside me to verify physically. So my reference to software was intentional. Anyway, that does not address my doubt.. On 9/29/05, KD5NWA <KD5NWA@...> wrote: The previous message that I answered was talking about the hardware (SR-40), you are talking about the software, two different subjects.
The previous message is talking about the signal being at 11KHz then it's read by the sound card, your talking about what happens after the sound card has read the signals.
Sorry for the confusion but we are talking about different things.
At 12:55 PM 9/29/2005, you wrote:
Cecil,
I just had a look at the powerSDR-SR40 code. Looking at sdr.c line, I can see that the signal is indeed at 11025 Hz. The RX oscillator runs at -11025 hz. Now, does that mean, the spectrum we can indeed tune to is centered around 7056-11.025 = 7044.9 khz? I am a bit confused here.
On 9/29/05, KD5NWA <KD5NWA@...> wrote:
The SoftRock itself doesn't convert all input signal to 11,250Hz, it has a fixed crystal oscillator, were the signal ends up depends where in the pass-band the original signal is. Some will be at 1KHz some at 5KHz, some at 19KHz depends on how far they are from the center of the pass-band (7.056MHz). A QRP signal a 7.040 will end up at 16KHz.
On the SDR1000 it's another story, they have a agile oscillator so they try to keep the signal you are tuned to at 11KHz away from the crud at at 0Hz.
At 11:26 AM 9/29/2005, you wrote:
--- In softrock40@..., w keith griffith <kgriffit@w...> wrote:
I have,,, 'SomeWhere' a really good description of the Weaver ssb method. There's a decent description of the Weaver method in the DSP section of all the recent ARRL Handbooks.
How, if at all, does that method compare with the softrock? The SoftRock itself does no demodulation. All it does is sample the incoming signal in such a way as to mix down to 11250Hz. The downconverted signal is then dumped to the computer's soundcard.
In the subsequent software DSP on the digitized signal, the SSB "demodulation" consists entirely of a bandpass filtering stage and another mixing stage to spin the signal centered at 11025Hz down to 0Hz.
CW is the same, except the mixing stage spins the signal down to the CW offset frequency (700Hz or whatever) rather than 0Hz.
73 Frank AB2KT
Yahoo! Groups Links
Cecil Bayona KD5NWA www.qrpradio.com
'Never argue with an idiot. They drag you down to their level then beat you with experience.'
Yahoo! Groups Links
-- 73 - Ramakrishnan, VU3RDD
Yahoo! Groups Links
Cecil Bayona KD5NWA www.qrpradio.com
'Never argue with an idiot. They drag you down to their level then beat you with experience.'
Yahoo! Groups Links
-- 73 - Ramakrishnan, VU3RDD
|
Re: Computer and Sound Card
The SantaCruz will be a fine card for the SoftRock. The software will surely work with it as it was the original card recommended by Flex-Radio with the SDR 1000.
The reason you're seeing a lot of Delta 44 recommendations these days is that it is the card that Flex is the primary card recommended by Flex-Radio. It's a 24 bit card and has very good specs. Plus it has 4 ins and 4 outs which works very will in a transceiver, no need to dork with mixers and switching when switching T/R.
For sound cards there are really 2 things that will affect how will it works with the SoftRock and PowerSDR. First is how good a card is it - S/N, # of bits etc. The second is how good are the drivers. This is more important for a transciever as it will need to go thru the driver to change ins/outs when going between transmit and receive. It is less important for a receiver, but the driver does need to basically work. Most (99%?) of them do - although there are some out there that will not. I've seen at least one USB sound card that has a bug that has the left and right channels off by 1 sample -- deadly for image suppression in something like PowerSDR.
My recommendation for folks with the SoftRock is to try whatever sound card you have on hand. Better sound cards will sound better, but most cards will work fine given one's expectation for a $23 kit.
Regards,
Bill (kd5tfd)
|
The other part of the equation is the computer and sound card. What is recommended ? I know that previous SDR discussion revolved around some of the better Creative Labs sound cards and at one time the Turtle Beach SantaCruz sound card was recommended as a good low noise card for SDR. Lately all I see recommended as the best card is the Delta 4? sound card. Since this SR40 really does not have the performance of the much better and more sophisticated SDR-1000, is the sound card selection all that important ? I did pick up a SantaCruz card at Fry's for $40 which is all I want to spend.
73 Kees K5BCQ
|
??? Finally got it.? NICE RECEIVER!!?? Went
through touching up pins on the IC's and the filter again. Hooked it up and
VOILA !!
?
?
Stan Rife W5EWA Houston, TX K2 S/N
4216 ?
toggle quoted message
Show quoted text
Hi Stan,
After
building over forty of the little SoftRock receivers I have seen what you
are talking about several times. With no signal at all getting through, it
usually is associated with the oscillator signal not being divided down to
clock the QSD quad switch.? Check carefully for open pins on the IC's and
solder bridges between IC pins.? Most of the time when a SoftRock
does not play right for me it is associated with a soldering
problem.
The usual things of making sure the right components are in
the right locations is fundamental.? Also check IC orientation.?
U1 for example has its pin 1 in the lower left corner of the IC when the
printing on the IC reads upright from left to right.
One time with
no signal getting thourgh I had a bad crystal which may have gone bad by
too much heat in soldering the grounding wire to the crystal case.?
Another time with no signal getting through the coax connector on the end
of the antenna coax had an internal short.
On the plus side, all
SoftRock40 units I have built have worked properly, some with extra
effort, with a baseline noise level of about -137 dBm when the unit is
calibrated for S9 (50 uV RMS) at -73 dBm.
I would be happy to chat on
the phone with you if you would like additional help.
73, Tony
KB9YIG ----- Original Message ----- From: "Stan Rife"
To: Sent:
Thursday, September 29, 2005 10:12 AM Subject: [softrock40] Not working:
HELP
> I finished the SoftRock last night and I plugged it in to
one of my > USB hubs...no green light from the LED. I put it back on the
bench and > verified everything and all looked ok. After messing with it
for a while > and > still not getting a green LED from my USB
hub, I decided to plug it in to > the USB on the back of the
computer...GREEN LIGHT. Wondering why the USB > hub > doesn't put
out 5 volts, but will worry about that later. I thought that >
the > 5 volts daisy chained from device to device. > So, it lit
up, but I am not receiving anything. The latest binary > was acting
really weird on my computer, so I reinstalled PowerSDR and then >
unzipped the binary's from August in to the SDR install. It appears to
> work > ok now, I think. I have no way of verifying that. All I
get is a little > background noise (I got this before though) and a
solid S-9 carrier at > 7.056, but this is ALL I ever got from the
software whenever I would start > it up with NO hardware. So, I hope
this is making sense, the SR-40 is > either > not working
properly, or the software is not working. > I can play the canned .wav
files and that works, but nothing from > the SR-40. Made sure my LINE-IN
port on the soundcard was selected, and > checked that the volume was up
sufficiently. I don't know what else to > check, or how to check it. I
am electronically challenged, sorry guys. > Plus > it is hard to
get back behind the PC to do anything. I don't have a 5 volt > power
supply. Can I use a 6 volt wall wart?? I didn't see a 5 volt >
regulator > on the SR-40. > Can someone tell me where to start?
And what about the S-9 carrier > at 7.056?? Is that supposed to be
there?? I do have an XG-1 signal source, > but I'm not getting anything
to the software. > > Thanks, > > Stan Rife >
W5EWA > Houston, TX > K2 S/N
4216 > > > > > > > Yahoo! Groups
Links > > > > > > >
|
??? Thanks Art. That is kind of what I suspected. I have
it plugged in to the back of the computer now and I do get
power.
?
Stan Rife W5EWA Houston, TX K2 S/N
4216 ?
toggle quoted message
Show quoted text
OK, OK..............
Can't stand it no
'mo...........
Your satellite USB port is not fully compatible. It's
not unusual, kinda like the old days when a PC was 99.9 IBM compatible,
but not quite:>:
The USB spec calls for 100 ma to be available to
the USB device connected to the port. However, the expansion ports
sometimes have little or no current available to run external
hardware.
Plug it into the main USB port, and it will run.
Plug
it into an expansion port and it might
not.
Regards,
Art
|
OK, OK..............
Can't stand it no 'mo...........
Your satellite USB port is not fully compatible. It's not unusual, kinda like the old days when a PC was 99.9 IBM compatible, but not quite:>:
The USB spec calls for 100 ma to be available to the USB device connected to the port. However, the expansion ports sometimes have little or no current available to run external hardware.
Plug it into the main USB port, and it will run.
Plug it into an expansion port and it might not.
Regards,
Art
|
Tony,
I sent you an email to your personal address. Yes, I could certainly use some
realtime help.
?
?
Stan Rife W5EWA Houston, TX K2 S/N
4216 ?
toggle quoted message
Show quoted text
Hi Stan,
After
building over forty of the little SoftRock receivers I have seen what you
are talking about several times. With no signal at all getting through, it
usually is associated with the oscillator signal not being divided down to
clock the QSD quad switch.? Check carefully for open pins on the IC's and
solder bridges between IC pins.? Most of the time when a SoftRock
does not play right for me it is associated with a soldering
problem.
The usual things of making sure the right components are in
the right locations is fundamental.? Also check IC orientation.?
U1 for example has its pin 1 in the lower left corner of the IC when the
printing on the IC reads upright from left to right.
One time with
no signal getting thourgh I had a bad crystal which may have gone bad by
too much heat in soldering the grounding wire to the crystal case.?
Another time with no signal getting through the coax connector on the end
of the antenna coax had an internal short.
On the plus side, all
SoftRock40 units I have built have worked properly, some with extra
effort, with a baseline noise level of about -137 dBm when the unit is
calibrated for S9 (50 uV RMS) at -73 dBm.
I would be happy to chat on
the phone with you if you would like additional help.
73, Tony
KB9YIG ----- Original Message ----- From: "Stan Rife"
To: Sent:
Thursday, September 29, 2005 10:12 AM Subject: [softrock40] Not working:
HELP
> I finished the SoftRock last night and I plugged it in to
one of my > USB hubs...no green light from the LED. I put it back on the
bench and > verified everything and all looked ok. After messing with it
for a while > and > still not getting a green LED from my USB
hub, I decided to plug it in to > the USB on the back of the
computer...GREEN LIGHT. Wondering why the USB > hub > doesn't put
out 5 volts, but will worry about that later. I thought that >
the > 5 volts daisy chained from device to device. > So, it lit
up, but I am not receiving anything. The latest binary > was acting
really weird on my computer, so I reinstalled PowerSDR and then >
unzipped the binary's from August in to the SDR install. It appears to
> work > ok now, I think. I have no way of verifying that. All I
get is a little > background noise (I got this before though) and a
solid S-9 carrier at > 7.056, but this is ALL I ever got from the
software whenever I would start > it up with NO hardware. So, I hope
this is making sense, the SR-40 is > either > not working
properly, or the software is not working. > I can play the canned .wav
files and that works, but nothing from > the SR-40. Made sure my LINE-IN
port on the soundcard was selected, and > checked that the volume was up
sufficiently. I don't know what else to > check, or how to check it. I
am electronically challenged, sorry guys. > Plus > it is hard to
get back behind the PC to do anything. I don't have a 5 volt > power
supply. Can I use a 6 volt wall wart?? I didn't see a 5 volt >
regulator > on the SR-40. > Can someone tell me where to start?
And what about the S-9 carrier > at 7.056?? Is that supposed to be
there?? I do have an XG-1 signal source, > but I'm not getting anything
to the software. > > Thanks, > > Stan Rife >
W5EWA > Houston, TX > K2 S/N
4216 > > > > > > > Yahoo! Groups
Links > > > > > > >
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Re: SSB demod, was Re: carrirer oscillator
The previous message that I answered was talking about the hardware (SR-40), you are talking about the software, two different subjects. The previous message is talking about the signal being at 11KHz then it's read by the sound card, your talking about what happens after the sound card has read the signals. Sorry for the confusion but we are talking about different things. At 12:55 PM 9/29/2005, you wrote: Cecil,
I just had a look at the powerSDR-SR40 code. Looking at sdr.c line, I can see that the signal is indeed at 11025 Hz. The RX oscillator runs at -11025 hz. Now, does that mean, the spectrum we can indeed tune to is centered around 7056-11.025 = 7044.9 khz? I am a bit confused here.
On 9/29/05, KD5NWA <KD5NWA@...> wrote:
The SoftRock itself doesn't convert all input signal to 11,250Hz, it has a fixed crystal oscillator, were the signal ends up depends where in the pass-band the original signal is. Some will be at 1KHz some at 5KHz, some at 19KHz depends on how far they are from the center of the pass-band (7.056MHz). A QRP signal a 7.040 will end up at 16KHz.
On the SDR1000 it's another story, they have a agile oscillator so they try to keep the signal you are tuned to at 11KHz away from the crud at at 0Hz.
At 11:26 AM 9/29/2005, you wrote:
--- In softrock40@..., w keith griffith <kgriffit@w...> wrote:
I have,,, 'SomeWhere' a really good description of the Weaver ssb method. There's a decent description of the Weaver method in the DSP section of all the recent ARRL Handbooks.
How, if at all, does that method compare with the softrock? The SoftRock itself does no demodulation. All it does is sample the incoming signal in such a way as to mix down to 11250Hz. The downconverted signal is then dumped to the computer's soundcard.
In the subsequent software DSP on the digitized signal, the SSB "demodulation" consists entirely of a bandpass filtering stage and another mixing stage to spin the signal centered at 11025Hz down to 0Hz.
CW is the same, except the mixing stage spins the signal down to the CW offset frequency (700Hz or whatever) rather than 0Hz.
73 Frank AB2KT
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Cecil Bayona KD5NWA www.qrpradio.com
'Never argue with an idiot. They drag you down to their level then beat you with experience.'
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Cecil Bayona KD5NWA www.qrpradio.com 'Never argue with an idiot. They drag you down to their level then beat you with experience.'
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Hi Stan,
After building over forty of the little SoftRock receivers I have seen what you are talking about several times. With no signal at all getting through, it usually is associated with the oscillator signal not being divided down to clock the QSD quad switch. Check carefully for open pins on the IC's and solder bridges between IC pins. Most of the time when a SoftRock does not play right for me it is associated with a soldering problem.
The usual things of making sure the right components are in the right locations is fundamental. Also check IC orientation. U1 for example has its pin 1 in the lower left corner of the IC when the printing on the IC reads upright from left to right.
One time with no signal getting thourgh I had a bad crystal which may have gone bad by too much heat in soldering the grounding wire to the crystal case. Another time with no signal getting through the coax connector on the end of the antenna coax had an internal short.
On the plus side, all SoftRock40 units I have built have worked properly, some with extra effort, with a baseline noise level of about -137 dBm when the unit is calibrated for S9 (50 uV RMS) at -73 dBm.
I would be happy to chat on the phone with you if you would like additional help.
73, Tony KB9YIG
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----- Original Message ----- From: "Stan Rife" <srife@...> To: <softrock40@...> Sent: Thursday, September 29, 2005 10:12 AM Subject: [softrock40] Not working: HELP I finished the SoftRock last night and I plugged it in to one of my USB hubs...no green light from the LED. I put it back on the bench and verified everything and all looked ok. After messing with it for a while and still not getting a green LED from my USB hub, I decided to plug it in to the USB on the back of the computer...GREEN LIGHT. Wondering why the USB hub doesn't put out 5 volts, but will worry about that later. I thought that the 5 volts daisy chained from device to device. So, it lit up, but I am not receiving anything. The latest binary was acting really weird on my computer, so I reinstalled PowerSDR and then unzipped the binary's from August in to the SDR install. It appears to work ok now, I think. I have no way of verifying that. All I get is a little background noise (I got this before though) and a solid S-9 carrier at 7.056, but this is ALL I ever got from the software whenever I would start it up with NO hardware. So, I hope this is making sense, the SR-40 is either not working properly, or the software is not working. I can play the canned .wav files and that works, but nothing from the SR-40. Made sure my LINE-IN port on the soundcard was selected, and checked that the volume was up sufficiently. I don't know what else to check, or how to check it. I am electronically challenged, sorry guys. Plus it is hard to get back behind the PC to do anything. I don't have a 5 volt power supply. Can I use a 6 volt wall wart?? I didn't see a 5 volt regulator on the SR-40. Can someone tell me where to start? And what about the S-9 carrier at 7.056?? Is that supposed to be there?? I do have an XG-1 signal source, but I'm not getting anything to the software.
Thanks,
Stan Rife W5EWA Houston, TX K2 S/N 4216
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