Date   

Re: Crystal CW filter with Version 4 uBITX boards? #ubitx

Ashhar Farhan
 

Allison,
The diplexer would have been required of we were concerned with mixer spurs. However the 45 mhz filter narrows the signals reaching the filter. So, mixer troubles by way of spurs are not a major concern.
The second filter frequency should not be harmonically related to 12 mhz. 4.195 mhz is a good choice. I have tried that and it worked very well.
I will make another build and post the details. 
- f

On 8 Jul 2018 9:34 am, "Jerry Gaffke via Groups.Io" <jgaffke=yahoo.com@groups.io> wrote:
Exactly how do the transformers ruin this?
The uBitx transformers are broadband.

I was imagining somehow holding both filters to 200 ohms, using only one set of transformers. 
That might be tough to do and still get the desired filter characteristics.
Though a CW filter may not need such a flat top.

Might be possible to have two sets of transformers in parallel.
The transformers don't have a fixed impedance, they just establish an impedance ratio.
So a high impedance into the filter should mean much higher than 50 ohms into that transformer.
Though all sorts of ways for this to trash performance.

I'd be fine with pluggable filters.
But am curious where dual filters would fail.

As your 45mhz-DialFreq spur shows, things can quickly go south in unexpected ways.
Measurements are  useful.
Even if it seems to work.

Jerry 


 

On Sat, Jul 7, 2018 at 04:51 pm, ajparent1/KB1GMX wrote:
The big difference is the lack of transformers it actually helps for that.  That version of the
bitx runs the amp interfaces at 200ohms.  In that case the unusd filter is not likely to
look like a rf short.  I wonder if the ubitx can be talked into running without the
transformers for the filter.  Either an L-network or none at all.  It may impact the
filter bandwidth and shape factor some.  I may test that for a single filter.

It should work but the choice of filter frequencies needs a little consideration to
avoid bleed though and spurs.  Things like non harmonically related and not
too close to the same frequency.



Re: NEXTION UPDATES FOR 7 AND 5 INCH - --ADAPTED FOR KD8CEC VER 1.095

Dave Dixon
 

Hi guys,
              I am thinking of adding a 2.4 screen to my Mbitx where can I buy a bezel for it please.regards Dave.

On 7 July 2018 at 18:26, Joe <joeman2116@...> wrote:
I just finished upgrade the nextion displays  to reflect the new release of KD8CEC V 1.095
Still more work to be done but fully functional .... always...LOL
7 and 5 inch
The 3.2 and 3.5  are being worked on

See attached files





VE1BWV
Joe



Unbuilt MicroBitx Kit for sale

w2ttt <w2ttt@...>
 

Hi Folks!
I have an unbuilt MicroBitx Kit that is just not getting my attention and needs to be sold off.
$110 shipped CONUS.
PayPal to w2ttt@... or Postal Money Order or check.
73,
Gordon Beattie W2TTT
201.314.6964
W2TTT@...


Re: MIC pins for amateurradiokits.in case

John Sharpe
 

That FB picture shows the amateurradiokits Front Panel Board. I don't have this board so my microphone wires come from the Digital plug on the Raduino.
Follow the HF signals diagram and see the wire colours there.



Re: Crystal CW filter with Version 4 uBITX boards? #ubitx

Jerry Gaffke
 

Exactly how do the transformers ruin this?
The uBitx transformers are broadband.

I was imagining somehow holding both filters to 200 ohms, using only one set of transformers. 
That might be tough to do and still get the desired filter characteristics.
Though a CW filter may not need such a flat top.

Might be possible to have two sets of transformers in parallel.
The transformers don't have a fixed impedance, they just establish an impedance ratio.
So a high impedance into the filter should mean much higher than 50 ohms into that transformer.
Though all sorts of ways for this to trash performance.

I'd be fine with pluggable filters.
But am curious where dual filters would fail.

As your 45mhz-DialFreq spur shows, things can quickly go south in unexpected ways.
Measurements are  useful.
Even if it seems to work.

Jerry 

 


On Sat, Jul 7, 2018 at 04:51 pm, ajparent1/KB1GMX wrote:
The big difference is the lack of transformers it actually helps for that.  That version of the
bitx runs the amp interfaces at 200ohms.  In that case the unusd filter is not likely to
look like a rf short.  I wonder if the ubitx can be talked into running without the
transformers for the filter.  Either an L-network or none at all.  It may impact the
filter bandwidth and shape factor some.  I may test that for a single filter.

It should work but the choice of filter frequencies needs a little consideration to
avoid bleed though and spurs.  Things like non harmonically related and not
too close to the same frequency.


Re: MIC pins for amateurradiokits.in case

k5map@...
 

John,

Much thanks for your reply... I've attached a pic from FB page which shows different color wires.  Could you please match your wires in your post above to the ones in this pic?

73, Mike


Re: MIC pins for amateurradiokits.in case

John Sharpe
 

I wired my mic socket like this one - it is an old Kenwood standard.
 
The ubitx wiring is Violet and Blue = microphone with the blue being the grounded side.
In my arrangement Violet goes to pin 1 abd Blue to pin 4. 
 
Orange is the PTT line and goes to pin 2. Pin 3 is grounded near the socket.
 
You can wire it any way you like as long as it matches the mic/ptt connections in the four-pin plug.
You have to make sure these match. I’m using a cheap Baofeng mic which I rewired.
 
73, John
 
 
 
Related image
Image result for 4-pin mic socket  kenwood


Re: HEX files with Mac OS

Bill Watkins
 

Avrdude, verbose output while loading another code, mac terminal,  copy and paste.  Finally!

Thanks for the tips and the patience.

https://forum.arduino.cc/index.php?topic=410618.0

Bill
K0WHW


DSA815-TG spectrum analyzer upgrade.

Glenn
 

For those that have this popular SA, and it wasn't bought recently, there is a free upgrade available for it, to improve the resolution bandwidth (RBW) from 100Hz to 10Hz.

Its easy to do, just follow the instructions included in the download.

https://int.rigolna.com/products/spectrum-analyzers/dsa800/

Glenn
vk3pe


Re: W8TEE Power/SWR Sketch for Nano

Mark M
 

That's the problem sometimes with written stuff like this...you can't see the grin or the smirk or the wink so sometimes it doesn't come across as intended, that's where the smilies, etc come in.

Anyway, keep us posted on progress, I'm sure this will be another popular kit...if it works. ;)

73.... Mark AA7TA

On 7/7/18 6:51 PM, Kees T wrote:
OK, I understand ...and it was funny. I blame the misinterpretation on my Dutch background. When I was in grade school and giving a weekly "news report" at the front of the class, I asked the teacher if I could discuss a second news item. She said "No, Kees, you might be stepping on someone's toes". I said, "Oh no, Mrs xxx. I wouldn't be stepping on someone's toes, just talking".
73 Kees K5BCQ


Re: uBitX on 24v?

Howard Fidel
 

If you are running on +24V I would change C98 and C99 to 35V parts, they won't last very long on 24VDC.
Howard

On 7/7/2018 10:09 PM, ajparent1/KB1GMX wrote:
Yes!  Keep it under 3.5A  it may want more but max power under needs to be kept under 30W.

Doing that the heat sinks are too small by a large margin.    When I do that the sink is typically
4x6 (flat surface) x1.25(height of fins) or larger.  You will need heatsink compound and insulator
kit.  Heatsink must be grounded.

Also the rest can be run at 12V.

Allison



MIC pins for amateurradiokits.in case

k5map@...
 

I purchased one of the amateurradiokits.in cases and I'm very pleased with it... 

I've begun the assembly using the parts included in the case.  One such part is the 4-pin MIC connector.  I've read his FB page but he does not show sufficient detail which shows which MIC pin connects to the PCB board.  Does anyone have a pic of the MIC connector showing which pins connect to their other end on the front PCB?

Mike / K5MAP


Re: uBitX on 24v?

ajparent1/KB1GMX <kb1gmx@...>
 

Yes!  Keep it under 3.5A  it may want more but max power needs to be kept under 45W.
The max dissipation is 43W per device so when your DC input is 86W your maxed
out and heat will be the bigger problem.  If the efficiency is decent you get about
45W maybe 55W on 40M.  I doubt you will get that much as the driver is a bit weak
so maybe 35W.   You may have to tweak the output transformer for operating under
those conditions to get that power or it may top out lower.

Doing that the heat sinks are too small by a large margin.    When I do that the sink is typically
4x6 (flat surface) x1.5"(height of fins) or larger.  You will need heatsink compound and insulator 
kit.  Heatsink must be grounded.   That may present mechanical issues, but that the fun.

Also the rest can be run at 12V.

Allison


Re: W8TEE Power/SWR Sketch for Nano

Kees T
 

OK, I understand ...and it was funny. I blame the misinterpretation on my Dutch background. When I was in grade school and giving a weekly "news report" at the front of the class, I asked the teacher if I could discuss a second news item. She said "No, Kees, you might be stepping on someone's toes". I said, "Oh no, Mrs xxx. I wouldn't be stepping on someone's toes, just talking".  

73 Kees K5BCQ


Re: Crystal CW filter with Version 4 uBITX boards? #ubitx

 

Gilles : 

I just installed the SOTABEAMS CW Filter (1Khz / 300 Hz) into my uBITX v3.  I  just removed the Green Wire from the audio
pot and connected that to the input of the filter and then I connected the output of the filter back to the 
the terminal on the pot that previously had the green wire via a 0.1uF capacitor to ensure that it is decoupled from the audio
amp as I believe that there may be DC voltages present on the filter output. 

Actually I have it wired up using a 3PDT switch to allow me to control the power to the filter board and to switch the 
filter in and out (bypass). I have a separate toggle switch to control the WIDE/Narrow selection.  I do recommend
adding the signal LED as it is a very useful tuning aid. It will flash with the received CW signal when it is in
the filter passband.  

One other point.  There is an option to increase the gain of the filter by grounding PIN 2 of the filter.
I found that this seems to work a lot better. I have less hiss in the audio as I don't need to increase the
volume as much, so I recommend doing this. 

I have done the same thing previously on my BITX40 and I can't say enough good things about these little filter 
modules. They are far better than any active CW filter I have ever used. 

Cheers

Michael VE3WMB


Re: W8TEE Power/SWR Sketch for Nano

Mark M
 

I was trying to be funny...it working is just a small detail. ;)

Mark

On 7/7/18 4:58 PM, Kees T wrote:
The only "details" I have are the schematic and the "N-1" board layout which are both in the "Files" section under my call.


Re: W8TEE Power/SWR Sketch for Nano

Kees T
 

The only "details" I have are the schematic and the "N-1" board layout which are both in the "Files" section under my call.

73 Kees K5BCQ


Re: Crystal CW filter with Version 4 uBITX boards? #ubitx

ajparent1/KB1GMX <kb1gmx@...>
 

The big difference is the lack of transformers it actually helps for that.  That version of the
bitx runs the amp interfaces at 200ohms.  In that case the unusd filter is not likely to
look like a rf short.  I wonder if the ubitx can be talked into running without the
transformers for the filter.  Either an L-network or none at all.  It may impact the
filter bandwidth and shape factor some.  I may test that for a single filter.

It should work but the choice of filter frequencies needs a little consideration to
avoid bleed though and spurs.  Things like non harmonically related and not
too close to the same frequency.

Allison


Re: W8TEE Power/SWR Sketch for Nano

Mark M
 

Details, details... :)

Mark AA7TA

On 7/7/18 3:50 PM, Kees T wrote:
Sure.....once we find out if the thing works.
73 Kees K5BCQ


Re: W8TEE Power/SWR Sketch for Nano

Lowell Haney NE4EB
 

Kees, put me down for five assemblies if this moves forward.

Lowell