Date   
Re: uBitx low signals on the speaker

Júnior PY2ADA
 

bingo !!!!!!!
Really the problem was it is in vfo CLK # 2
I inserted the rf generator at approximately 52Mhz and now we have the normal operation of ubitx.
Probably some defect in SI5351.
Lucky I have another raduino board.
I leave here my contribution to who in the future find this same defect, and that apparently would be the TDA2822 and was not.

73 de Júnior
 
 
 

Re: Blew the irf510's up, substituted irfp260's in there place... #ubitx-help

John Backo
 

Greg:

If you are aware of what happened, just get new deices and install them.
You probably will need to redo the alignment as IRF510s are notoriously
variable. You CAN let the adjustments alone, but you will never be sure
of their real value. If you have ever changed them from the factory settings,
you must re-do the adjustments.

The simplest way is to set RV1, RV2, and RV3 to zero, using a DVM and RF
probe. Then, install the new devices. Then check what the RCVR current draw is
with the DVM. It should be somewhere around 100 ma. But it doesn't matter
much what it is as long as RCV is working. Check the antenna SWR to make
sure it is ok (below 2.0:1) Connect the PA drain voltage -- there should be little or
no change in current draw. Make sure the antenna is connected. While in transmit, SLOWLY
increase RV2 until there is an additional current draw of about 100 ma. SLOWLY
increase RV3 until there is an additional current draw of 100 ma. The RX draw
should be about the same; the idle TX draw is an additional 200 ma. or so.

Then, in TX, speak into the mike with a long "aaahh" while SLOWLY increasing RV1.
The current drain should increase another ampere or so. That should be close
to your final adjustment. You can tweek RV1 a bit until actual distortion occurs;
if that happens back off RV1 a hair until things are clear. (having a QSO to check
your audio helps a lot).

And there you are. You can check the voltage (carefully!) on the gates in TX.
They both should be around 3v, and should match fairly well if the devices you
installed were from the same place and time of manufacture. After that, let
well enough alone.

Incidentally, the same procedure applies for almost any MOSFETS installed as
PA finals.

Hope this helps.

john
AD5YE

Low power output on ubitx

Mike R.
 

First post - be gentle :)
I have been playing around with the ubitx for about a week now. Pretty cool radio and I like the idea of modifying the software.
Installed Ian's version of the software v1.04 and even added a menu entry on my own to display the current version which normally only appears at power up. Still have a ways to go in fully understanding the software for the rig.
To the point...I was listening to some FT8 the other night and enjoying the decoding on the computer screen from the ubitx. I thought it might be nice to see if I could transmit. So, I connected a dummy load and wattmeter to see if the rig was putting out power. I tried CW first.
I had VERY low power out, in the range of milliwatts.
The numbers:
Frequency: 7.150, antenna connected to a dummy load.
Power supply set to 12.5 volts. Using a key to send CW.
Output was nil on 40m. Didn't make the meter move on the WM-1.
So, I did the bias adjustment thing that everyone says to not do. Adjusted the bias for the 510's at 100ma each and then set RV3 max clockwise (how it was received, actually).
Output on 40M was about 400mw after adjusting the bias and RV3.
Started to dig into Glenn's post where he made measurements of the PA section. Everything was nominal to his
numbers except for the collector voltages on Q92-93 and 96-97 where they were 12V vs. the 2.8v he measured.
I get 12v on the "TX" side of R961 and 11V on the junction of R961 and C92.
Receive current is about 160ma and transmit current is around 720ma for an output of about 400mw.
I'm thinking there is something amiss with T10.
Any comments for anyone that has had the same issue and found a resolution?
Thanks, Mike W1USN



Re: Soldering gun or iron

Roy Appleton
 

I don't do a lot of SMD projects and so I don't use a mask just manually apply the solder paste from a syringe that the paste came in. My advice is that you can't have too small a nozzle. In the attached photo I use the cone shaped one because the black one is too big. You'd be surprised how little paste you need before you make a big mess! My source for paste isn't available any more so don't have any suggestions but I'm sure it's not hard to find sources.

Roy
WA0YMH

On Mar 16, 2018 2:04 PM, "Christopher Miller" <djmalak2k6@...> wrote:
How do you apply the paste? I dont have a way to create a mask for a pcb. You also make a good point. If you have a heat gun you can use shrink wrap. Thats a great reason to get a hot air rework station with an iron.

Re: Soldering gun or iron

Don WB4AFP
 

I finally treated myself to a Hakko 888D to replace my 30-year-old Weller with regulation in the tip.  The difference is night and day.  The Hakko heats practically instantly and lets you know when it has, and the regulation is much tighter.  Soldering is much quicker and more repeatable that way.  For me, well worth the $100.  As a noob, your learning curve and pile of destroyed parts will be way smaller.

All a soldering gun can do with surface mount parts on a tight board is destroy everything.  Don't even try.

Seeing the teensy parts is another problem whether you are a noob or not.  I got a pair of 3x reading glasses at Dollar Tree for $1, which focus at about 6", and they work as well as the hood magnifiers.  For $1 you can have spares and not worry if you touch the lens with the soldering iron.  They're not as good as my 10x stereo microscope, but that cost almost $400.

The other essential is good tweezers.  Get non-magnetic ones made for electronic assembly.  I always end up putting tweezers down next to a magnet somehow.  They get magnetized and stick to ferrite inductors and some other parts like glue -- usually just long enough to transfer them to the floor where they bounce around to land under something hard to move.

Re: uBitx low signals on the speaker

Mike Woods
 

Substituting the Raduino to eliminate the problem suggests this was another case of oscillators beating together in mixers to give rise to annoying audio tones.

Mike ZL1AXG

On 17/03/18 10:58 AM, Júnior PY2ADA via Groups.Io wrote:
bingo !!!!!!!
Really the problem was it is in vfo CLK # 2
I inserted the rf generator at approximately 52Mhz and now we have the normal operation of ubitx.
Probably some defect in SI5351.
Lucky I have another raduino board.
I leave here my contribution to who in the future find this same defect, and that apparently would be the TDA2822 and was not.

73 de Júnior
 
 
 


--
Mike Woods
mhwoods@...

Re: Soldering gun or iron

Roy Appleton
 

Doesn't look like the photo made it the first time.

Re: PCB Price Comparison tool

Kerr Smith
 

This site is definitely worth using when you are looking to get PCBs made. The last time I used it it suggested ALLPCB which had an offer on at the time so I got 5 boards for $5 with free courier shipping (my PCBs arrived in 5 days).

I would highly recommend using the site to see which PCB fabricators are currently the cheapest, you can then do a bit of research and get some user reviews and decide if you want to get your boards made with them.

There are so many different PCB manufacturers this site makes it really easy to get an initial price per PCB for lots of them with you only needing to enter in some basic data such as PCB size and number required etc.

Solving problem with when plugging in a headphone causing a shorted to ground of C77 470uF to ground and may damage U1 TDA2822

ve7hcw@...
 

If you don't use a  speaker  with your uBITx and use only a headphone. best idea is to add a 1K resistor to the negative lead of C77 (470uF capacitor) to charge the capacitor slowly when  first power up. Now when you insert the headphone ,any accidental shorting of the sleeve and tip to ground will not create a surge  from the U1 TDA2822 since  c77 is already charged by the 1K resistor. this will prevent a loud pop on your headphone as well as possible damage to the audio amp chip.

wayne 72

Re: PCB Price Comparison tool

Terry VK5TM
 

I would take the pricing with a grain of salt, the results showed a price double what I recently paid to have an order made from one of the China fabs.

Re: Ordering date, shipping date, Ordering date, received date

Vince Vielhaber
 

Awww. It just tires you right out, huh?

Vince.

On 03/16/2018 05:25 PM, Thomas Sharka via Groups.Io wrote:
I'm willing to bet that the interest in when it was ordered, when it was
shipped, when it arrived on a doorstep is only shared for a short time
by a very few.

Ashar knows what he's doing, we don't need a blow by blow. These
"status" messages are only cluttering up a very busy group To top it
off, it gets very tiring having to delete so many "status" messages over
the course of a week.

Just my two cents.



Sent from Yahoo Mail. Get the app <https://yho.com/148vdq>


On Friday, March 16, 2018 4:53 PM, Vince Vielhaber <vev@...> wrote:


Actually some folks do, especially the ones wondering when theirs will
ship. If it bothers you, delete it and move on.

Vince.



On 03/16/2018 03:28 PM, Ken Brown wrote:
There are multiple messages on BITX of an ordering date, shipping date,
or ordering date and received my BITX date. Do you think everyone wants
to know your ordering date, shipping date, or your received date, or
your not-received date of your BITX?

Ken


<http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
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<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
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http://www.CDupe.com/ <http://www.cdupe.com/>
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<http://www.metalworkingfun.com/>





Compressor, Expander, and ALC or ACG

James Lawrie
 

Hello,

Due to family issues I have not posted in a while but I have ordered parts for my experiments with Bitx. Two items of note that others may want to play with are:

SA575DTBG Low Voltage Compandor ON Semiconductor 

 

SA571DG Compandor ON Semiconductor


Both are dual channel compressor/ Expanders and of obvious note is the SA575DTBG because it offers ALC....

When I get back I do plan on trying them with my Bitx 40. Haven’t gotten to my UBitxs yet but work for them too.

I bought mine from mouser wher you can also see data sheets with examples.

Maybe the fix for others blues, and there pretty cheap as well.

Jim

Re: Ordering date, shipping date, Ordering date, received date

Thomas Sharka
 

I give my 2 cents and you gave me something else.

Thanks Vince.
 


Sent from Yahoo Mail. Get the app


On Friday, March 16, 2018 8:18 PM, Vince Vielhaber <vev@...> wrote:


Awww. It just tires you right out, huh?

Vince.



On 03/16/2018 05:25 PM, Thomas Sharka via Groups.Io wrote:
> I'm willing to bet that the interest in when it was ordered, when it was
> shipped, when it arrived on a doorstep is only shared for a short time
> by a very few.
>
> Ashar knows what he's doing, we don't need a blow by blow. These
> "status" messages are only cluttering up a very busy group To top it
> off, it gets very tiring having to delete so many "status" messages over
> the course of a week.
>
> Just my two cents.
>
>
>
> Sent from Yahoo Mail. Get the app <https://yho.com/148vdq>
>
>
> On Friday, March 16, 2018 4:53 PM, Vince Vielhaber <vev@...> wrote:
>
>
> Actually some folks do, especially the ones wondering when theirs will
> ship.  If it bothers you, delete it and move on.
>
> Vince.
>
>
>
> On 03/16/2018 03:28 PM, Ken Brown wrote:
>> There are multiple messages on BITX of an ordering date, shipping date,
>> or ordering date and received my BITX date.  Do you think everyone wants
>> to know your ordering date, shipping date, or your received date, or
>> your not-received date of your BITX?
>>
>> Ken
>>
>>
>>
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>>    Virus-free. www.avg.com
>>
> <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
>>
>>
>> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>>
>
> --
>  Michigan VHF Corp.  http://www.nobucks.net/ <http://www.nobucks.net/>
> http://www.CDupe.com/ <http://www.cdupe.com/>
>                          http://www.metalworkingfun.com
> <http://www.metalworkingfun.com/>
>
>
>
>
>
>

--
  Michigan VHF Corp.  http://www.nobucks.net/   http://www.CDupe.com/
                          http://www.metalworkingfun.com





Re: Soldering gun or iron

Michael Hagen
 

Great Place for Solder and SMD Supplies!

72's Mike, WA6ISP

https://www.cmlsupply.com/


On 3/16/2018 3:27 PM, Roy Appleton wrote:
I don't do a lot of SMD projects and so I don't use a mask just manually apply the solder paste from a syringe that the paste came in. My advice is that you can't have too small a nozzle. In the attached photo I use the cone shaped one because the black one is too big. You'd be surprised how little paste you need before you make a big mess! My source for paste isn't available any more so don't have any suggestions but I'm sure it's not hard to find sources.

Roy
WA0YMH

On Mar 16, 2018 2:04 PM, "Christopher Miller" <djmalak2k6@...> wrote:
How do you apply the paste? I dont have a way to create a mask for a pcb. You also make a good point. If you have a heat gun you can use shrink wrap. Thats a great reason to get a hot air rework station with an iron.

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...

Look in the "Files" section here.

Jeffrey Benedict
 

There is a wide variety of antenna possibilities listed in the Files section here.

Both the uBitx and the Bitx40 are easy to assemble. The one area that might be a hang up is the case.  In order to make a case, you need some metal working skills and tools. However, it is possible to buy a case customized so the boards and accessories fit right in and it comes with some of the other things needed to get it together.  A soldering iron, a couple of screwdrivers, some wire cutters and a 4" Crescent wrench  will get it together for you.  Some of these cases are on e-bay and some of the other usual sources.

Re: RD16HHF1 power curve flattening...some

K9HZ <bill@...>
 

Hey Nick… did you make any progress?  I’ve been dying to dig into this but work keeps getting in the way of playing with my radios.  That’s gotta stop!

 

Something is up.  You can actually put another secondary winding on the PA transformer for negative feedback… That’s actually preferred.

 

I ran a couple simulations and the whole thing is stable without the feedback though (slightly lower gain though).

 

I sure like the 20+ watts out of those RD16 HHF1’s though and they are bullet proof.  I’ve never blown one out, and I’ve designed a lot of amplifiers with them and made a lot of mistakes with the “ON” switch in the “GO” position.

 

 

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

 

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

 

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com

Like us on Facebook! facebook icon

 

Moderator – North American QRO Yahoo Group.

 

email:  bill@...

 

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Nik VK4PLN
Sent: Sunday, March 11, 2018 6:55 PM
To: BITX20@groups.io
Subject: Re: [BITX20] RD16HHF1 power curve flattening...some

 

Well, i have dont my mods and powered up. Results are mixed:
Here are the mods.
RD16 replace IRF510.
New output transformer 1:4 BN43-3321 with a 330pf cap on input.
feed back resistors. from 22ohm to 1 K ohm
piggy backed R87 and R88 with 220pf capacitor.
RV1 full drive.

So results.
80M - 20W + ( blew my 2 Amp fuse)
40M - 18W - Seems stable.
30M - 17W BUT I get BAD feedback/ oscillation by just going PPT with no voice. The watt meter goes up to 18W!
20M - 15W  -  Same feedback issue
15M -  Same feedback issue.
10M -  Same feedback issue.

I have been thinking ans looking at other RD16 schematics, in alot of cases they dont use the feedback on the finals?
Also could this issue be cuase in the driver stage?

THanks guys, I am in over my head here....

73
10M - Same feedback issue


Virus-free. www.avg.com

Re: Low power output on ubitx

Conrad San Diego
 

Hi Mike I had the same problem.  I checked Q90 and found E & B are shorted. I replaced 2N3904 with a regular type transistor Instead of the SMD type. I get 30 W but I tuned it down to 15 W.


On Fri, Mar 16, 2018, 17:20 Mike R. <ubitx@...> wrote:
First post - be gentle :)
I have been playing around with the ubitx for about a week now. Pretty cool radio and I like the idea of modifying the software.
Installed Ian's version of the software v1.04 and even added a menu entry on my own to display the current version which normally only appears at power up. Still have a ways to go in fully understanding the software for the rig.
To the point...I was listening to some FT8 the other night and enjoying the decoding on the computer screen from the ubitx. I thought it might be nice to see if I could transmit. So, I connected a dummy load and wattmeter to see if the rig was putting out power. I tried CW first.
I had VERY low power out, in the range of milliwatts.
The numbers:
Frequency: 7.150, antenna connected to a dummy load.
Power supply set to 12.5 volts. Using a key to send CW.
Output was nil on 40m. Didn't make the meter move on the WM-1.
So, I did the bias adjustment thing that everyone says to not do. Adjusted the bias for the 510's at 100ma each and then set RV3 max clockwise (how it was received, actually).
Output on 40M was about 400mw after adjusting the bias and RV3.
Started to dig into Glenn's post where he made measurements of the PA section. Everything was nominal to his
numbers except for the collector voltages on Q92-93 and 96-97 where they were 12V vs. the 2.8v he measured.
I get 12v on the "TX" side of R961 and 11V on the junction of R961 and C92.
Receive current is about 160ma and transmit current is around 720ma for an output of about 400mw.
I'm thinking there is something amiss with T10.
Any comments for anyone that has had the same issue and found a resolution?
Thanks, Mike W1USN



Re: [uBiTx] last frequency memory?

Mike Hoddy
 

Thanks Ashhar, I didn’t realise it was that simple!  

Keep up the good work, I’m an experienced amateur having started as a listener in 1967 aged 11 with boatanchor sets (still have a few) but I’ve been having so much fun with your BiTX and now the ubitx, it’s like being back to those times and learning!

73 de Mike, G0JXX

Finally finished boxing up my uBitX #ubitx

Michael Aiello
 

After about 8 weeks of working on it slowly, a few minutes at a time, I've finally finished boxing up my uBitX and it's now up and running FB.
 
The box and mic holder are 3d-printed from a design I found on Thingiverse and remixed a bit. 
 
I've made a few mods along the way:
  • replaced failed WX TDA2822 with a NJM2073D pin-compatible chip
  • rewired power to put fuse ahead of protective diode
  • added QRPGuys keying adapter
  • upgraded firmware to KD8CEC v1.01
  • increased mic gain by added 47 ohm resistor across R63
I'm primarily interested in CW, so I tried out my NesCAF switched capaacitance audio filter with the rig -it works great! The NesCAF was built from a kit years ago, and has been languishing on a shelf, but it will get used now daily.
 
I've had a lot of fun with this little rig already just putting it together, I'm looking forward to getting on the air with it a regularly. 
 
73,
Mike N2HTT
 

Re: PCB Price Comparison tool

denm178@...
 

Check out Oshpark for pcb prices.
73 Dennis