This are the TDA2822Ms I received from China ordered on eBay 
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Re: Raduino oscilators. 33mhz and 57mhz " . Documentation says one thing, but this is what I measured.
Cool guys. Yes, glad I wasn't actually going insane. lol
On Wed, Mar 7, 2018 at 1:40 PM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote: Wasn't obvious to me from your first post what you had measured that was different than Farhan's explanation.
Sounds like you may have found that 33mhz is LSB and 57mhz is USB instead of the other way around?
Looking at Farhan's C code, I believe you are correct.
I wasn't being very careful is saying which was which, and Farhan quite likely was doing the same.
Just that the uBitx switches between USB and LSB by putting clk1 at 12mhz on the other side of the 45mhz IF.?
Would take me 5 minutes of pencil to paper to convince myself one way or the other on the uBitx. Here's what Farhan has to say in the comments for his source file ubitx_20.ino, note the #define's at the end:
/**
?* The uBITX is an upconnversion transceiver. The first IF is at 45 MHz.
?* The first IF frequency is not exactly at 45 Mhz but about 5 khz lower,
?* this shift is due to the loading on the 45 Mhz crystal filter by the matching
?* L-network used on it's either sides.
?* The first oscillator works between 48 Mhz and 75 MHz. The signal is subtracted
?* from the first oscillator to arriive at 45 Mhz IF. Thus, it is inverted : LSB becomes USB
?* and USB becomes LSB.
?* The second IF of 12 Mhz has a ladder crystal filter. If a second oscillator is used at
?* 57 Mhz, the signal is subtracted FROM the oscillator, inverting a second time, and arrives
?* at the 12 Mhz ladder filter thus doouble inversion, keeps the sidebands as they originally were.
?* If the second oscillator is at 33 Mhz, the oscilaltor is subtracated from the signal,
?* thus keeping the signal's sidebands inverted. The USB will become LSB.
?* We use this technique to switch sidebands. This is to avoid placing the lsbCarrier close to
?* 12 MHz where its fifth harmonic beats with the arduino's 16 Mhz oscillator's fourth harmonic
?*/
// the second oscillator should ideally be at 57 MHz, however, the crystal filter's center frequency
// is shifted down a little due to the loading from the impedance matching L-networks on either sides
#define SECOND_OSC_USB (56995000l)
#define SECOND_OSC_LSB (32995000l)
?
?
On Wed, Mar 7, 2018 at 01:08 pm, Michael Shreeve wrote:
Well, you've gave me the Farhhan explanation at his site :??"To invert the sideband between USB and LSB, the second oscillator is switched between 33 MHz and 57 MHz.
-- Michael Shreeve N6GRG
15901 Cloverdale Road
Anderson, CA 96007
530-410-8678
"Don't worry about a thing, 'Cause every little thing gonna be all right!" -Bob Marley
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HI Qonita,
I haven't seen any other replies so I'll throw in my two cents. If you already have the information you need you may safely ignore this post! :)
WSPR is a low-speed protocol which really doesn't have anything to do with GPS. I assume this is also true for WSJTX.
You could theoretically connect a GPS module that uses serial communications. Arduinos have built-in UARTs just for this purpose, and it's very easy to send and receive serial data through the existing USB serial interface to/from a host computer. However, you don't want to use the USB connection- you probably want a direct serial connection.
Looking at the Arduino Nano schematic shows that the TxD and RxD lines are also brought in parallel to two IO pins, so you can theoretically connect low-level serial lines directly between the two. I haven't tried this myself, though, hence the word "theoretically".
If you wish to check for yourself, the Arduino Nano schematics are available at several places- for example,
.
IMPORTANT: Serial communications sometimes use RS-232 levels. These are NOT compatible with the Arduino pins! RS-232 involves higher positive voltages and negative voltages which will likely damage an Arduino. You are looking for a GPS module with so-called "TTL compatible" serial lines.
Hope this helps, Chris B, AC9GN
On Tue, Mar 6, 2018 at 7:24 AM, <qonita.salimah@...> wrote: Can we adding GPS module and receive GPS coordinat data with BITX? I've heard of WSPR and WSJTX method, but not really understand about that.
Thank you so much :)?
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Re: Connection to the raduino
What rig are you talking about, the Bitx40 or the uBitx?
The Bitx40 has a 5 wire connector soldered into one end of the line of 16 holes at the bottom of the raduino,
A cable assembly plugs into that providing 12v to the Raduino and CLK2 into the Bitx40 board.
On the uBitx, this has been replaced by a 16 right angle header pins.
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On Wed, Mar 7, 2018 at 01:20 pm, @dsbl1886 wrote:
According to the instructions and the parts list there is a 5 pin connector that attaches to the back of the Raduino, I have to wiring but there is no place to connect it on the Raduino. Has this been eliminated?
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Re: Raduino oscilators. 33mhz and 57mhz " . Documentation says one thing, but this is what I measured.
Wasn't obvious to me from your first post what you had measured that was different than Farhan's explanation. Sounds like you may have found that 33mhz is LSB and 57mhz is USB instead of the other way around? Looking at Farhan's C code, I believe you are correct. I wasn't being very careful is saying which was which, and Farhan quite likely was doing the same. Just that the uBitx switches between USB and LSB by putting clk1 at 12mhz on the other side of the 45mhz IF.?
Would take me 5 minutes of pencil to paper to convince myself one way or the other on the uBitx. Here's what Farhan has to say in the comments for his source file ubitx_20.ino, note the #define's at the end:
/**
?* The uBITX is an upconnversion transceiver. The first IF is at 45 MHz.
?* The first IF frequency is not exactly at 45 Mhz but about 5 khz lower,
?* this shift is due to the loading on the 45 Mhz crystal filter by the matching
?* L-network used on it's either sides.
?* The first oscillator works between 48 Mhz and 75 MHz. The signal is subtracted
?* from the first oscillator to arriive at 45 Mhz IF. Thus, it is inverted : LSB becomes USB
?* and USB becomes LSB.
?* The second IF of 12 Mhz has a ladder crystal filter. If a second oscillator is used at
?* 57 Mhz, the signal is subtracted FROM the oscillator, inverting a second time, and arrives
?* at the 12 Mhz ladder filter thus doouble inversion, keeps the sidebands as they originally were.
?* If the second oscillator is at 33 Mhz, the oscilaltor is subtracated from the signal,
?* thus keeping the signal's sidebands inverted. The USB will become LSB.
?* We use this technique to switch sidebands. This is to avoid placing the lsbCarrier close to
?* 12 MHz where its fifth harmonic beats with the arduino's 16 Mhz oscillator's fourth harmonic
?*/
// the second oscillator should ideally be at 57 MHz, however, the crystal filter's center frequency
// is shifted down a little due to the loading from the impedance matching L-networks on either sides
#define SECOND_OSC_USB (56995000l)
#define SECOND_OSC_LSB (32995000l)
?
?
On Wed, Mar 7, 2018 at 01:08 pm, Michael Shreeve wrote:
Well, you've gave me the Farhhan explanation at his site :??"To invert the sideband between USB and LSB, the second oscillator is switched between 33 MHz and 57 MHz.
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Re: Raduino oscilators. 33mhz and 57mhz " . Documentation says one thing, but this is what I measured.
According to the documentation the 1st oscillator tunes from 45 to 75 MHz to receive 0 to 30 MHz. Since the oscillator is higher than the received frequency this inverts the sidebands. LSB becomes USB. Since the bfo is below the filter passband we receive whatever is above it. 33 MHz is below the 45 MHz IF so does not inverts the sidebands. So it gives us LSB. 57 MHz is above the IF so the sidebands are inverted again and we receive USB.
So in short what you measure should be right.
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Connection to the raduino
According to the instructions and the parts list there is a 5 pin connector that attaches to the back of the Raduino, I have to wiring but there is no place to connect it on the Raduino. Has this been eliminated?
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Re: Raduino oscilators. 33mhz and 57mhz. Documentation says one thinng, but this is what I measured.
Ok, checked out the BITX40 explanation, and clearly the uBITX is a completely different giraffe and requires different math. If someone even wanted to try to do that I'd be grateful. I guess I might be able to wrap my head around it.
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Re: Raduino oscilators. 33mhz and 57mhz " . Documentation says one thing, but this is what I measured.
Well, you've gave me the Farhhan explanation at his site :??"To invert the sideband between USB and LSB, the second oscillator is switched between 33 MHz and 57 MHz. " But that's clearly not whats happening. So , I'm hoping someone else would measure what I have measured. LSB used 33 and USB used 57 . Works very well, as I have said, sounds perfect. Yes, I'll look at the bITX40 explanation.
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Re: TDA2822 experiments and mods
Sounds perfect.
Let us know when it's done, and we'll all pile on to criticize your grammar.
Many thanks for setting up that website!
Jerry
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On Wed, Mar 7, 2018 at 12:56 pm, Mike Woods wrote:
I decided to both amend the original story () and add a news item about Raj's experiment ()
I now need to write up a synthesis article (appearing in the main menu), on audio amp fixes given this is probably an ESSENTIAL mod for those with the WX chips (although if I had one in, I would be replacing it with another TDA2822).
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Re: Raduino oscilators. 33mhz and 57mhz. Documentation says one thinng, but this is what I measured.
I hate sitting through videos.?
The math involved is addition and subtraction,? no need to solve any differential equations.
The 12mhz crystal filter has a 3dB passband of around 11.996 to 11.998 mhz, something like that.
The BFO on clk0 should be roughly 500hz away from the passband, so either 11.9955 or 11.9985 mhz.
Will vary from rig to rig, crystals get sorted by frequency so each rig has a matched set of crystals for the filter.
Original plan had been to switch the BFO between high and low side when selecting USB vs LSB.
But the 11.9985 mhz BFO had harmonics that beat with the 16mhz harmonics from the Nano processor,
so Farhan elected to freeze the BFO at 11.9955 mhz.? Instead moves the second oscillator
between 33 and 57 mhz when selecting between USB and LSB.
The VFO is always 45mhz higher than the operating frequency.
Here's an old discussion of how it worked on the Bitx40, using very round numbers to make it easy to follow:
? ??/g/BITX20/message/24724
Jerry, KE7ER
?
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On Wed, Mar 7, 2018 at 12:24 pm, Michael Shreeve wrote:
And first of all, this uBITX works perfectly. It sounds great. Its very sensitive and has good tone quality. Literature says this :?"To invert the sideband between USB and LSB, the second oscillator is switched between 33 MHz and 57 MHz. " . If usb matches with 33 and lsb matches with 57 which it does at the site here : (clearly on the diagram where it clearly says 33 usb, 57 lsb, then its time to do the math ? So I checked very clearly the radio in the next video. Block diagram is here. Ashhar says we should do the math. Now, if I can figure out how to do that math, its another video lol.
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Re: TDA2822 experiments and mods
Jerry
I decided to both amend the original story
() and add a news
item about Raj's experiment
()
I now need to write up a synthesis article (appearing in the main
menu), on audio amp fixes given this is probably an ESSENTIAL mod
for those with the WX chips (although if I had one in, I would be
replacing it with another TDA2822).
Mike ZL1AXG
On 8/03/18 4:52 AM, Jerry Gaffke via Groups.Io wrote:
Looks like a fine
solution.
The fact that the 78L09 inherently limits current to something
reasonable is a bonus.
And fits in there perfectly!
Might be a little bit easier to just rip that trace out entirely.
Could place the part up against the through-hole on one side,? run
a short wire to the other through-hole.
Gain should remain as it was at 12v.??
Just that when you turn the volume up it distorts sooner.
If what you have on hand is the TO220 LM7809 (or any voltage from
5v to 9v),
it will fit in there nicely as well.? Glue it face down to the
board with pins hovering over
the trace that Raj has cut:
? ??/g/BITX20/message/43463
Or, if you don't like glue, solder a short wire from tab to ground
plane.
If Mike Woods is with us here, he can now update his webpage to
state the hack is proven:
? ??/g/BITX20/message/43467
Jerry, KE7ER
On Wed, Mar 7, 2018 at 04:52 am, Raj vu2zap wrote:
Solution 3: 78L09. the center lead looks soldered but
it is floating but the tab is soldered to the copper
below it. The white wire is my fix for prevent the filter relays
from clicking during PTT. Yes the board
needs a brush cleaning!
The audio is fine but distorts at high volume. The 9V voltage
out does not drop at max volume.
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Raduino oscilators. 33mhz and 57mhz. Documentation says one thinng, but this is what I measured.
And first of all, this uBITX works perfectly. It sounds great. Its very sensitive and has good tone quality. Literature says this :?"To invert the sideband between USB and LSB, the second oscillator is switched between 33 MHz and 57 MHz. " . If usb matches with 33 and lsb matches with 57 which it does at the site here : (clearly on the diagram where it clearly says 33 usb, 57 lsb, then its time to do the math ? So I checked very clearly the radio in the next video. Block diagram is here. Ashhar says we should do the math. Now, if I can figure out how to do that math, its another video lol.
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Re: The issues of the TDA2822
I must be gettin really old. I read it and didn't even think twice about it till Jerry mentioned it.
Vince.
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On 03/07/2018 02:21 PM, Arv Evans wrote: Jerry
Good catch...yes, I am an old geezer. Meant to say "emitters" but the
fingers
typed "cathodes" instead. Hopefully newer hams will understand.
Arv
_._
On Wed, Mar 7, 2018 at 11:31 AM, Jerry Gaffke via Groups.Io
<jgaffke@... <mailto:jgaffke@...>> wrote:
As per
<>
You're dating yourself with that cathodes thing.
But most of us are old enough to follow.
Jerry
On Wed, Mar 7, 2018 at 10:21 am, Arv Evans wrote:
Possibly use an op-amp for the audio pre-amp and follow it with
an NPN-PNP
pair. Feedback from the NPN-PNP cathodes to input of the op-amp
(with resistive
divider to set gain) and you have a composite replacement for
integrated audio
amplifiers.
--
Michigan VHF Corp.
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Re: RD16HHF1 to replace 510's in Micro BITX
Hi Graham, Have a look here:??
Marco - KG5PRT
On Wed, Mar 7, 2018 at 1:23 PM, Graham W <gram.warrington@...> wrote: Hi.. Building up the UbitX. I am thinking of replacing the 510's with the RD16HH ' s .
Does anyone have some tips on doing this?? Appreciate any tips on doing so.
I do know the pinout is different...
Thanking you for any help.
Graham VE3WGW
-73-
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RD16HHF1 to replace 510's in Micro BITX
Hi.. Building up the UbitX. I am thinking of replacing the 510's with the RD16HH ' s .
Does anyone have some tips on doing this?? Appreciate any tips on doing so.
I do know the pinout is different...
Thanking you for any help.
Graham VE3WGW
-73-
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Re: The issues of the TDA2822
Jerry
Good catch...yes, I am an old geezer.? Meant to say "emitters" but the fingers
typed "cathodes" instead.? Hopefully newer hams will understand.?
Arv
_._
On Wed, Mar 7, 2018 at 11:31 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote: As per? ??
You're dating yourself with that cathodes thing.
But most of us are old enough to follow.
Jerry
On Wed, Mar 7, 2018 at 10:21 am, Arv Evans wrote:
Possibly use an op-amp for the audio pre-amp and follow it with an NPN-PNP
pair.? Feedback from the NPN-PNP cathodes to input of the op-amp (with resistive
divider to set gain) and you have a composite replacement for integrated audio
amplifiers.
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Re: The issues of the TDA2822
I just have to chime in and let you all know how much I appreciate being able to see this type of dialog.? Every message a link to go read about, every part number a new thing to discover.? My uBITX has paid for itself several times over already through learning and discovery and it hasn't even shipped.
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Re: DIY Anderson Powerpole Connector Panel Mount
$9.00 each with shipping.
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I've got a BITX40 that I got about 6 months ago and haven't had time to assemble yet, now I ordered (early Feb) a uBitx since I think it may be a better solution for backpacking with HF
Still waiting on shipping notification from paypal, judging by others timelines, I'll probably get that notification in early april and receive it around my birthday in mid april.
On Wed, Mar 7, 2018 at 10:02 AM, John KG9DK <jab3739@...> wrote: I got the heads up form PayPal that my uBit has shipped.? Ordered on Jan. 8,2018, almost 2 months to day.? I still have wire up the Bit40, plus other projects, I am probably the only ham that has that problem...? Will the group know when I receive the package.
john kg9dk
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Michael Shreeve