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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Re: The issues of the TDA2822
As per? ??
You're dating yourself with that cathodes thing.
But most of us are old enough to follow.
Jerry
toggle quoted message
Show quoted text
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: DIY Anderson Powerpole Connector Panel Mount
You can find 'em a lot cheaper here:
3 bucks plus shipping,? about $4.50. Buy more save money. (That statement makes no sense!)
Bill K3ONO
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Re: uBitX Working but bad audio
Umm, yes.
If you wire the phone jack such that the audio out is going to both tip and ring,
then plug in a mono plug with just tip (and sleeve at ground),
then the audio out gets shorted to ground, and you get no sound at all.
I guess headphones with stereo plug would sound "better" than no sound at all.
Depending on individual preferences.
My significant other generally prefers the latter when it comes to ham gear.
Jerry
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On Wed, Mar 7, 2018 at 09:40 am, <jrromes1@...> wrote:
The message # for the problem with using a mono plug for the speaker is #42601
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Re: The issues of the TDA2822
Farhan
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.
This could be an interesting small circuit board for use in many projects, or even
as a stand-alone audio amp for the workbench.
Arv
_._
On Wed, Mar 7, 2018 at 2:01 AM, Ashhar Farhan <farhanbox@...> wrote: John, others,
Given our experience of the non-generic ICs going out of production, it is best to stick to either discrete or generic ICs. The bitx20 will soon be a 15 year old design. The NorCal is probably older and still being built. We will have to choose parts that are going to be around for a long time, that are easily substituted. This means, we must work with large design margins, discrete or generic ICs.?
Given these limitations, we are pretty much limited to either op-amps or discrete devices.?
Opinions?
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Re: Micro BitX No Audio TDA2822?
Ron N4RT
Scroll to the bottom for the full schematic.
Arv? K7HKL
_._
On Wed, Mar 7, 2018 at 8:32 AM, Ron Thomas <n4rt@...> wrote: Ok, I am new to this group and have just assembled my micro bitx.? I sent an earlier message to the group explaining that I have no audio.?
After reading some of the posts regarding the TDA2822 chip, is it possible that I have somehow blown the audio amp while plugging in headphones or external speaker using the supplied audio jack?
I've not heard any noise from the speaker or headphones at any time... no pops or other noises at all.
The rig powers up and appears to tune just fine (I haven't tried to transmit yet) but after not getting any audio, I stopped at that point.
Where should I probe with voltmeter or oscope to see where I'm losing audio?? Any troubleshooting tips anyone could share would be most appreciated.
Is there a schematic of the board somewhere that I can download?
Sorry for all the questions but I don't know much about this rig.
73,
Ron N4RT
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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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Re: uBitX Working but bad audio
What's this reference?
My guess is that they are telling you that in the bridge configuration of the TDA2822M
where both halves are used out of phase, you must use a stereo jack to external speaker.
Take a look at the TDA2822M datasheet and all should be clear, neither wire to the speaker can be grounded
when in bridge configuration.
However, the uBitx uses only one channel of the part, so it's ok if one of the speaker wires is grounded.
I can believe that switching to $200 Bose headphones improved the sound.
They have some really nice headphones.
Jerry, KE7ER
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On Wed, Mar 7, 2018 at 09:36 am, <jrromes1@...> wrote:
Hi David,
I have the TDA2822M in mine.? I found a reference where they indicated that you must use a stereo plug for an external speaker.? I was using a Kenwood SP23 thinking quality but found it had a mono plug on it which is advertised as a no no.? I switched to Bose headphones and my audio cleared considerably.? I'm thinking that was possibly a major cause of some of my problem.? Stay tuned!!
73,
John WW3JR
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Re: uBitX Working but bad audio
David,
The message # for the problem with using a mono plug for the speaker is #42601
J
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Re: TDA2822 experiments and mods
ST makes the 78L** parts in a SOT-89 package.
Same package as U2, the 78L05 for the IRF510 gate bias.
TI and Fairchild LM78L** parts only come in the SOIC-8 and TO-90 (also some dinky BGA that we don't want to talk about).
Digikey and Mouser don't sell ST's SOT-89, so a bit harder to obtain.
The SOIC-8 should do fine, solder the ground pins to the ground plane for heat transfer.
The TO92 could work, though likely heat up faster cuz the heat has nowhere to go.
Yes, I'd expect the max available current from a 78L09 to limit maximum audio level.
Though apparently enough audio for Raj, and limiting that current does protect the 2822.
If it gets to be too much current for the 78L09, it will shut down till it cools off.
Just what we want, if it's enough audio power for your situation.
If you want more power and less protection, use the 1 Amp TO220 LM7809 (or 08 or 06 or 05) face down, flat on the board.
ST sells the 1 Amp L78** in the Dpak/TO252 package, about the same as the TO220.
TI sells the 500ma? LM78M** in the Dpak/TO252 package, might be an ideal solution for moderate levels of current.
Any of the above could be made to work, any regulator from 5 to 9 volts.
Assuming you don't have one of the clones made from factory floor sweepings that smokes at 7v.
I tried following the power traces around, I believe cutting the trace Raj shows in his picture
only affects the TDA2822.? However, it's possible some other section of the uBitx is also getting
voltage reduced, this should be checked for.
Jerry, KE7ER
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On Wed, Mar 7, 2018 at 08:24 am, Tim Gorman wrote:
I like this solution.
I can't quite see what is printed on your unit but it seems to be an
SOT-89 type package. I can't find any 7809 units in that configuration.
I can find them in the D2pak or the to252-3 style. I assume either of
those would work as well?
You say you used a 70L09 but aren't those only rated to about 100ma?
That wouldn't seem to be high enough to handle heavy loads from the
2822.
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Re: uBitX Working but bad audio
On Tue, Mar 6, 2018 at 04:52 pm, N8DAH wrote:
TDA2822
Hi David, I have the TDA2822M in mine.? I found a reference where they indicated that you must use a stereo plug for an external speaker.? I was using a Kenwood SP23 thinking quality but found it had a mono plug on it which is advertised as a no no.? I switched to Bose headphones and my audio cleared considerably.? I'm thinking that was possibly a major cause of some of my problem.? Stay tuned!! 73, John WW3JR
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""just a total malapropism (look that up!)
WOW! How did you know i had to? It is a gift right? Is it because I'm Canadian living among the Ameriglish/Yankish? It is really no big deal. I make grammatical errors all the time but I joint the Royal Canadian Regiment when I was 17. I think that is an awesome excuse. Others have their excuses. Maybe quit school to feed the little brothers and sisters? Or as the Brits call them, adorable urchins. Cherry Hoe!
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Re: The issues of the TDA2822
How about the wiper of the volume pot?
Vince.
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On 03/07/2018 12:07 PM, Paul Smith wrote: For my part I'd be happy with the provision of an audio take-off
connector on board. That way I can run whatever drop-in module or
external powered speaker I like.
Paul ZS2OE
--
Michigan VHF Corp.
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Michael Shreeve
John KG9DK
John R