Re: Raduino oscilators. 33mhz and 57mhz. Documentation says one thinng, but this is what I measured.
From what I read its not a bitx20 or 40, so the math shown appleis to a single conversioon receiver.
The microbitx ubitx is very different as its DUAL CONVERSION. So any math shown is just plain
wrong to a degree.? ?Yes you can flip the 3rd oscillator for sideband change or the second of for
that fact is the oscillator can do? it the first!
First all signals are converted to the 45mhz first IF, makes no different if its 1.8mhz or 144mhz save for the?
1st LO is going to be above the IF or below it.? The second mixer and associated 2nd LO are being switched from?
45MH-12mhz=~33 or 45+12mhz=~57mhz and can be used to switch what sideband is in use just as easily as
flipping the 11.9978(give or take) and 12.500(also give or take).? The trick is if you take 45-33 your get -12?
(the minus means inversion in frequency in this case) or its 45-57 or 12 note the sign is positive or no inversion.
Also the fact that the first IF filter is 45mhz means images are not an issue all the way up to 432/450mhz or higher
as the image frequency is 90mhz away and easily filtered.? So with a decent RF (LNA) and appropriate filters?
VHF and UHF are possible with the same basic design though the Local osc the 1st may requires a multiplier
stage to reach UHF.? ? Its an positive artifact of using a high IF so the radio can tune the whole HF range without
switching filters other than the required low pass output filters.? Its a simplification of what most commercial
(YaIcKen) HF radios do.
Allison/kb1gmx
YaIcKen is Yaesu/Icom/Kenwood.
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Re: RD transistors, unobtanium?
HI Farhan.
Does this mean V2 uBitx will have RD16HHF1 ??!?!
LOl, thanks,
73.
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Re: Raduino oscilators. 33mhz and 57mhz. Documentation says one thinng, but this is what I measured.
Plenty of errors to be found in comments and documentation, including mine.
Better off obsessing with how it works than what the documentation says.
> WOW. Has this always been there ??
Been there for awhile.
I doubt it's "trivial".
And for UHF, I'd use an Si5338 or Si5341 instead of messing with doubling the Si5351,
But yes, seems reasonable to do.
You can get years of tinkering out of that $109 investment,
if that's what you're looking for.
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On Wed, Mar 14, 2018 at 05:54 pm, Michael Shreeve wrote:
Well, wrong or right isn't what I'm looking for, but the basic detail I was interested in here:?
Likewise, a high side clk1 of 56995000 hz? for USB always flips the sidebands when translating to 12mhz,
however the low side clk1 of 32995000 hz we use to receive the 7.2mhz LSB signal does not:
corresponds to what I measured basically. The high 57 is used for usb, and the low 33 is used for lsb.
And of course, that doesn't match (at least last I looked) what Ashhar says. The description text is a little vague, but the block diagram specifically says 33 for usb, 57 for lsb. Maybe just a typo, but not sure.?
If my counter is on freq, which I still haven't determined, the frequencies I'm measuring seem to indicate that possibly each raduino is matched to the radio, and the master clock actual frequency wouldn't be so important if some of the calibration routines are used. The radio would still be fairly accurate. I should know soon. thanks again.
A part of Ashhars writeup that I did not notice before is down below,?
"?VHF/UHF coverage?With the 45 MHz IF, it is trivial to build band-pass filters with microstriplines for 144 MHz, 220 MHz and 432 Mhz frequencies. The Si5351’s clock may not high enough for the first conversion directly at 432 Mhz but a sub-harmonic mixer that works with only half the local oscillator frequency can easily scale this rig for VHF/UHF work. MMICs like the MAR6 series and power modules from Mitsubishi can easily scale this radio to reasonable performance level for weak signal and satellite work."?
WOW. Has this always been there ??
?
?
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Re: USB interface cable installation uBITX
There are two tiny metal "tabs" or fingers in the arduino-nano mini-USB socket that can get hooked into the plug when it is first inserted (has happened to two different Chinese made nanos in our club). This will prevent the plug from going in far enough to make contact. They must be carefully pried up out of the way (don't accidentally hook one of the contact springy wires in the socket). Usually if you can get the plug to properly go in once, the little fingers will be bent up enough and won't cause further problems.
AL? VE3RRD
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Yes, his numbers are off.
Filter passband on the Bitx40 is around 2000 hz wide,
3 dB passband might be 11996000 to 11998000, within a khz or so,
depending on which bin the crystals for his rig were picked from.
BFO is probably best placed maybe 500 hz beyond that,
so 11995500 for USB and 11998500 for LSB.
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On Wed, Mar 14, 2018 at 05:37 pm, Tim Gorman wrote:
I'm not sure what your frequencies mean. 11994420 - 11984800 = 12000
and 11996450-11984800 = 9620.
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Re: Raduino oscilators. 33mhz and 57mhz. Documentation says one thinng, but this is what I measured.
Well, wrong or right isn't what I'm looking for, but the basic detail I was interested in here:?
Likewise, a high side clk1 of 56995000 hz? for USB always flips the sidebands when translating to 12mhz,
however the low side clk1 of 32995000 hz we use to receive the 7.2mhz LSB signal does not:
corresponds to what I measured basically. The high 57 is used for usb, and the low 33 is used for lsb.
And of course, that doesn't match (at least last I looked) what Ashhar says. The description text is a little vague, but the block diagram specifically says 33 for usb, 57 for lsb. Maybe just a typo, but not sure.?
If my counter is on freq, which I still haven't determined, the frequencies I'm measuring seem to indicate that possibly each raduino is matched to the radio, and the master clock actual frequency wouldn't be so important if some of the calibration routines are used. The radio would still be fairly accurate. I should know soon. thanks again.
A part of Ashhars writeup that I did not notice before is down below,?
"?VHF/UHF coverage?With the 45 MHz IF, it is trivial to build band-pass filters with microstriplines for 144 MHz, 220 MHz and 432 Mhz frequencies. The Si5351’s clock may not high enough for the first conversion directly at 432 Mhz but a sub-harmonic mixer that works with only half the local oscillator frequency can easily scale this rig for VHF/UHF work. MMICs like the MAR6 series and power modules from Mitsubishi can easily scale this radio to reasonable performance level for weak signal and satellite work."?
WOW. Has this always been there ??
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Re: Ubitx audio debug question
Rod, Do your headphones have a stereo/mono switch? If so just unwire the speaker lead going to the ring contact on the audio jack and set your headphones to mono. That's what I am doing (actually I used a mono jack instead of a stereo jack). Then if I plug in a speaker using a mono plug everything will be copacetic. tim ab0wr On Wed, 14 Mar 2018 10:31:10 -0700 "WA9GQT via Groups.Io" <WA9GQT@...> wrote: I was very cautious and finally got the uBITX?wiring correct after
looking at all the posts.? It was receiving great until I unplugged
my headphones and plugged in a speaker.? I fried U1!? My speaker plug
was not stereo it was mono plug!? So that's why U1 audio amp fried.
So I just ordered 2 TDA2822M's from Amazon.com.? I am unable to use
the uBITX until I replace U1. I am very upset about this audio
circuit design!? This circuit seems to be the Achilles heal of this
radio, including a?very loud popping between?receive/ transmit.? I
would?like to use a speaker in the future.? I will?be sure to be very
careful of the wiring of any?speaker.? I hope to have my first
contact soon!
A very unhappy
Rod, WA9GQT
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I'm not sure what your frequencies mean. 11994420 - 11984800 = 12000 and 11996450-11984800 = 9620. These don't match your 2030hz and 4060hz figures. If your crystals all average out to about 11984800hz then any bandpass filter will have a frequency just a little above that frequency. Let's assume it will run from 2khz to 5khz higher, i.e. a 3khz bandwidth or from 11986800hz to 11989800hz. I thought the bitx40 used a 5Mhz vfo and a 12Mhz if (i.e. crystal filter frequency)? Why are you adding a 12Mhz (vfo offset) to the frequency? And then using another 12Mhz (usbCarrier) signal to demodulate it? You just wind back up with a signal of 7Mhz. Am I misunderstanding what you are doing? There is a reason for shifting the vfo frequency. To make the best use of a crystal filter, which typically has a steeper cutoff at the lowest frequency and a less steep cutoff at the upper frequency, usually LSB signals are converted to USB signals where the audio frequencies higher in frequency than the carrier. tim ab0wr On Wed, 14 Mar 2018 01:54:42 -0700 "Ryan Flowers" <geocrasher@...> wrote: Hello Everyone,
I've been working on my own digital VFO/BFO for my BITX40. The goal:
Switch sidebands without inverting the VFO to 19mhz for 40M and 26mhz
for 20M. I've got it working, mostly, but I'm having one heck of a
time with audio quality. The 12mhz crystals not 12mhz but rather
11,984,800 and currently I have my sidebands at 11994420 for USB and
11996450 for LSB. These are 2030 and 4060hz away from the crystal
frequency, and I am having a hard time visualizing how that works.
But at any rate, these are the what I came up with mostly through
trial and error.?
I'm currently using a modified version of the uBITX sketch. I've
added the offset frequency (11984800, named vfoOffset) and lsbCarrier
and am using the following to do my tuning:
if (isUSB){ si5351bx_setfreq(0, vfoOffset + frequency);
si5351bx_setfreq(1, usbCarrier); } else{ si5351bx_setfreq(0,
vfoOffset + frequency); si5351bx_setfreq(1, lsbCarrier); } I've also
added menu items for adjusting the USB/LSB and Offset easily, and
using these I adjusted for best inbound audio and ended up with the
aforementioned values. When I tune the radio to 7074mhz and select
USB, I'm not getting *any* decodes on FT8- but it works on LSB...
What on earth? The other thing is that audio output (as tested by
transmitting into a dummy load and listening on my Kenwood) is just
terribly choppy and unintelligible. I've tried varying the signal
output strength of the si5351 clocks from 2ma to 8ma, no difference.
It sounds terribly over-modulated.
I have gotten in over my head, but I'm determined. Can somebody help
me understand this so I can not just complete this project but get a
better understanding??Thanks so much.
--?
Ryan Flowers - W7RLF
MiscDotGeek.com ( )
Multi Band BITX40 ( )
The BITX40 FAQ ( )
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Re: Encoder details from various suppliers
Of all of those links, only the last one is any good. All of the others do not have a threaded shaft, which most people will want. I've probably purchased 50 KY-40 encoders and all have worked well. I haven't used them all, so there may be a bad one lurking in the pile, but so far, so good. These do have a detent, but another post here showed how to make it "detentless". Personally I like the detent as it stops on a dime and there is no coasting.
Jack, W8TEE
From: Michael Shreeve <shreevester@...>
To: [email protected]
Sent: Wednesday, March 14, 2018 8:14 PM
Subject: [BITX20] Encoder details from various suppliers
I've looked at encoders which I believe are used in the uBITX .? Perhaps you need one, they can be blown up with incorrect hookups, or physically just bad. Or perhaps your doing a special project and need one.?
Of course, the encoder supplied with a uBITX is kind of a special animal.?
It has the following specs. or close to it. There are a couple of important details, one the Number of Detent, and the Important spec is "without" and? , a few do not have switches and a few details like that. The link for a table showing these specs is here.?
And here is the encoder I believe to be almost exactly what we use in the Raduino .?
Now, if you try to get encoders, its really tough on ebay. Most of the details are left out. And, my experience with some listings is that if they give the details, it will be a very expensive item.? Here for example.?
From England,? GPB 8.99 $12.67 US Dollars for ONE !?
Most of the ebay listings are like this one. Cheap, but no details.
And, you will be very disappointed because one of the most important details is the encoder is the "number of detents" which should say "without". Detents are the physical click you feel when you turn it, uBITX encoders are smooth, no detents, and Alps says "without" to describe this feature. Encoders with Detents are terrible for the uBITX.? And most likely the ones supplied by Ebay will have detents.?
?And Amazon doesn't give any details either.?
I am told these would be like the ones the uBITX uses.?
But, I'm not sure how the person who referred this to me knew that. Definitely not from the listing. Was he just? lucky ??
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Re: USB interface cable installation uBITX
Nice! Where did you get the plug/adapter?
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Encoder details from various suppliers
I've looked at encoders which I believe are used in the uBITX .? Perhaps you need one, they can be blown up with incorrect hookups, or physically just bad. Or perhaps your doing a special project and need one.?
Of course, the encoder supplied with a uBITX is kind of a special animal.?
It has the following specs. or close to it. There are a couple of important details, one the Number of Detent, and the Important spec is "without" and? , a few do not have switches and a few details like that. The link for a table showing these specs is here.?
And here is the encoder I believe to be almost exactly what we use in the Raduino .?
Now, if you try to get encoders, its really tough on ebay. Most of the details are left out. And, my experience with some listings is that if they give the details, it will be a very expensive item.? Here for example.?
From England,? GPB 8.99 $12.67 US Dollars for ONE !?
Most of the ebay listings are like this one. Cheap, but no details.
And, you will be very disappointed because one of the most important details is the encoder is the "number of detents" which should say "without". Detents are the physical click you feel when you turn it, uBITX encoders are smooth, no detents, and Alps says "without" to describe this feature. Encoders with Detents are terrible for the uBITX.? And most likely the ones supplied by Ebay will have detents.?
?And Amazon doesn't give any details either.?
I am told these would be like the ones the uBITX uses.?
But, I'm not sure how the person who referred this to me knew that. Definitely not from the listing. Was he just? lucky ??
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On Wed, Mar 14, 2018 at 04:07 pm, Doug W wrote:
With the money you'll save on the advice you just got you can afford a good book.
This one? is recommended by many.
Besides it's hard to go wrong with the author of the book a big supporter of the forum. Leonard kc0wox
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I didn't notice it too much myself until someone pointed it out.? Now it drives me crazy.? Was thinking if I am going to build an audio filter I might as well socket the MX TDA2822 and mount the IC to board with a voltage regulator and a bandpass filter. May try to make it a plug in module that fits into the DIP socket.
--
Jason Schlager
KM6AUS
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Either is probably good enough.
Both is best.
We don't really know much about the WX except that many have blown in the uBitx.
I'd tend to replace the chip.
There are reports on the web that some of the TDA2822 clones work fine
at 5 or 6v, and blow when you go much higher.
The WX seems to be one of those, so just a regulator is probably good enough.
Let us know if you find out otherwise.
Jerry
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On Wed, Mar 14, 2018 at 04:27 pm, Joe Puma wrote:
Thanks Vince so should it be replaced completely or should add a regulator, or both?
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On Fri, Mar 2, 2018 at 03:50 pm, Clark Martin wrote:
You could use the second audio amp in U1. ?The TDA2822 is a dual amplifier. ?What you’d need to do is this:
?
Remove R75
Connect U1-6 to VOL-H. ?This will give you an auxiliary sound output that is independent of the volume control.
Connect the + terminal of a 470 ?F, 16V electrolytic capacitor to U1-3.
Connect the - terminal of the above cap to your auxiliary out mini jack.
?
The 470 ?F could very likely be much smaller, depending on the input impedance of your Signal Link.
Experiment, it won’t hurt.
?
You may also want to add a resistor divider between the cap and jack to reduce the signal strength, depending on how much your Signal Link can tolerate.
?
Considering the problem others are having with the TDA2822 you probably should add a resistor in series with the cap, unless you implement the resistor voltage divider, that will provide the same protection.
On Mar 2, 2018, at 10:20 AM, Walter < W9KJO@...> wrote:
On Wed, Feb 28, 2018 at 09:47 am, Richie Chambless wrote:
Yes, the yellow wire is the full signal from the product detector. Check your volume potentiometer to ensure it’s connected to the end (orange should be on middle lug). I would think your external amplifier has a capacitor input on it, so I don’t think another cap is necessary. Check to see if DC is present across the volume pot when the side tone is activated.
Ok The yellow wire does not have enough audio for my Signal Link to work with.? it showed some signals.? I have to reconnect to the 3.5mm Audio Out jack and turn the volume up about half way.? which is too loud for my headphones so I need to install a second 3.5mm for my Head Phones.??I would be much better if I could find a way to get enough audio separate from the actual audio out to the 3.5mm jack
How would I set up this resistor divider? ? -- 73, W9KJO Walter
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Uh-oh. . . . . . ???
Roy WA0YMH
On Mar 14, 2018 5:48 PM, "Joe Puma" < kd2nfc@...> wrote: Ordered Jan 17th. Got shipping notice 2 days ago and it showed up today in NY.
I’m 623/3
This is my TDA chip, am I safe? Lol
Now to get a cool case. ??
Joe
KD2NFC
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Re: Raduino oscilators. 33mhz and 57mhz. Documentation says one thinng, but this is what I measured.
Nope.
But that's what the code says it does.
I'll be very surprised if it's wrong.
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On Wed, Mar 14, 2018 at 04:21 pm, Michael Shreeve wrote:
Jerry, have you actually measured the frequencies of ck 2, ck 1, and ck 0 at specific frequencies, say 7.2 lsb if you would like. So far no one has reported their results.?
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Thanks Vince so should it be replaced completely or should add a regulator, or both?
Joe
KD2NFC
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On Mar 14, 2018, at 7:02 PM, Vince Vielhaber <vev@...> wrote:
Are you safe? Nope. That's a WX chip. I have the same chip except the lettering is almost unreadable.
Vince.
On 03/14/2018 06:48 PM, Joe Puma wrote:
Ordered Jan 17th. Got shipping notice 2 days ago and it showed up today in NY.
I’m 623/3
This is my TDA chip, am I safe? Lol
Now to get a cool case. ??
Joe
KD2NFC
--
Michigan VHF Corp.
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Re: Raduino oscilators. 33mhz and 57mhz. Documentation says one thinng, but this is what I measured.
Jerry, have you actually measured the frequencies of ck 2, ck 1, and ck 0 at specific frequencies, say 7.2 lsb if you would like. So far no one has reported their results.?
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With the money you'll save on the advice you just got you can afford a good book.
This one? is recommended by many.
|
Nick VK4PP
Michael Shreeve
Jason Schlager