Date   
Re: Replacing the PA section on Bitx 40

 

Here is how I made the socket and mounted the RDD16

Note the RDD is reversed and  then the gate is actually soldered to the IRF gate line which goes behind the FET.
Now I can use either of them..

You will need to think of a heat sink plate that fits this way!

Emacs!


At 01/02/2018, you wrote:
Why replace everything?  You can probably put it in place of the 510 (making sure it is pinned correctly, of course). Â
I am waiting on a pair, myself, that I will be stuffing into the ubitx.   I want to even out the power output.  I will also try a resistor/capacitor in parallel, in series with the gate, to try and even out the frequency response.  I am thinking 4.7 ohm & 4700pf.  I will also try 6.8 ohm & 4700pf.  Depends on how flat I can get the output.

Marco - KG5PRTÂ

On Jan 31, 2018 10:12 PM, "James Lawrie" <lawriejk@...> wrote:
Hello,
My shipment of replacement RF Mosfets have arrived and I want to replace the on board PASection with one based on the RD16HHF1. It will be a separate small PCB based on the reference design shown in the data sheet. I need help from the professionals here as to where to attach the new PA board.
I know it would be somewhere after the 2N2219A driver, and I want to remove all bypassed SMTs and or other parts from the Bitx board in that area. If you have a pretty good idea could you please let me know, and possibly a drawing if you could. This should keep me busy and off the forum for a while.

Re: Dynamic mic on ubitx

Dave Bottom <ars.kd6az@...>
 

Dennis,

Modifications to use a Dynamic Mic.
Referring to the uBITX Schematic.  The Gain of the Mic PreAmp is controlled by R63 in the Emitter of Q6 to C62/R64.  It basically decouples the audio bypass of R64 by C62 to limit gain for the high output Electret Mics.  Replacing R63 with a Zero Ohm resistor and putting a 10K at the Mic input should allow a Dynamic Mic to work now with a Mic Gain Control.  Also R60 that supplies Mic BIAS to the Electret-Condenser Mic needs to be removed.  If there is not enough Gain still, you might have to reduce the value of R64 to maybe 470 Ohms or so.  If you cannot look at your transmitted signal on a scope at least listen to your audio on another receiver to verify you are not causing distortion.

More Gain for the Electret Mic
To simply get more gain with an Electret Mic you might try dropping another 47 Ohm chip resistor on top of the existing R63 by soldering another chip resistor one end at a time.

Dave WI6R

On Wed, Jan 31, 2018 at 6:13 AM, Dennis Yancey <bigbluedry@...> wrote:
has anyone used a dynamic mic on the ubitx? If you have, please givedetails such aspiring, did you use any preamp, etc. also what were the results as reported by others?

thanks.




--
73 Dave WI6R

Re: Dynamic mic on ubitx

Marc Jones
 

Just put a DC Blocking cap in series , I use a old CB hand mic, Works fine .

On Wed, 31 Jan 2018 at 14:13, Dennis Yancey
<bigbluedry@...> wrote:
has anyone used a dynamic mic on the ubitx? If you have, please givedetails such aspiring, did you use any preamp, etc. also what were the results as reported by others?

thanks.

uBITX schema relay K1 #ubitx

pe0fko
 

Hello group,

After looking at the very nice schema of the uBITX (http://www.hfsignals.com/wp-content/uploads/2017/12/ubitxv3.pdf) i have a question about the K1 relay.
The K1 relay is used for the RX and TX power switching and also for connecting the antenna in RX to the LP filter.

On RX (and TX) the LP filter is also a connection to the TX power amp by C80, that will give a (very) small load on the antenna signal at RX and a mixer (Q90 diode BE) for strong received signals?
It can be changed by by switching the pins 12 and 14 of K1 and connection pin 16 of K1 to C80 (remove that one from the LP filter)?

I do not own a board (yet), so i cannot test it.
Maybe there are very well reasons for using it as it is, I did not read the total history.

73, Fred
pe0fko

Re: uBITX Firmware (CEC) 0.30 released (Test version). #ubitx

Andrew Farkas <afarkas@...>
 

Very nice. I wish I could figure out FT-8. I can't get anyone to comeback on my regular rig. These apps are very intricicate. Too bad there isnt some kind of standard for making radio software work.

Andy

VA3AAF

On Feb 1, 2018 3:19 AM, Kari Syrjänen <beaconhunter@...> wrote:
Ian's firmwares working great! I have been using then since version 0.25

Now running 0.33 and working 7MHz FT8-mode. Over 350 QSO.s in my logbook

TNX!

Kari OH5YW

Re: [SPAM] Re: [BITX20] Replacing the PA section on Bitx 40

K9HZ <bill@...>
 

I really like that!   If you fold the RD16 over you could use a heat sink out the back…

 

 

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

 

 

email:  bill@...

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Raj vu2zap
Sent: Thursday, February 01, 2018 4:24 AM
To: BITX20@groups.io
Subject: [SPAM] Re: [BITX20] Replacing the PA section on Bitx 40

 

Here is how I made the socket and mounted the RDD16

Note the RDD is reversed and  then the gate is actually soldered to the IRF gate line which goes behind the FET.
Now I can use either of them..

You will need to think of a heat sink plate that fits this way!

Emacs!

At 01/02/2018, you wrote:

Why replace everything?  You can probably put it in place of the 510 (making sure it is pinned correctly, of course). Â
I am waiting on a pair, myself, that I will be stuffing into the ubitx.   I want to even out the power output.  I will also try a resistor/capacitor in parallel, in series with the gate, to try and even out the frequency response.  I am thinking 4.7 ohm & 4700pf.  I will also try 6.8 ohm & 4700pf.  Depends on how flat I can get the output.

Marco - KG5PRTÂ

On Jan 31, 2018 10:12 PM, "James Lawrie" <lawriejk@...> wrote:

Hello,

My shipment of replacement RF Mosfets have arrived and I want to replace the on board PASection with one based on the RD16HHF1. It will be a separate small PCB based on the reference design shown in the data sheet. I need help from the professionals here as to where to attach the new PA board.

I know it would be somewhere after the 2N2219A driver, and I want to remove all bypassed SMTs and or other parts from the Bitx board in that area. If you have a pretty good idea could you please let me know, and possibly a drawing if you could. This should keep me busy and off the forum for a while.

Re: [SPAM] Re: [BITX20] Replacing the PA section on Bitx 40

K9HZ <bill@...>
 

Also… have you had it on the air like that yet?

 

 

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

 

 

email:  bill@...

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Raj vu2zap
Sent: Thursday, February 01, 2018 4:24 AM
To: BITX20@groups.io
Subject: [SPAM] Re: [BITX20] Replacing the PA section on Bitx 40

 

Here is how I made the socket and mounted the RDD16

Note the RDD is reversed and  then the gate is actually soldered to the IRF gate line which goes behind the FET.
Now I can use either of them..

You will need to think of a heat sink plate that fits this way!

Emacs!

At 01/02/2018, you wrote:

Why replace everything?  You can probably put it in place of the 510 (making sure it is pinned correctly, of course). Â
I am waiting on a pair, myself, that I will be stuffing into the ubitx.   I want to even out the power output.  I will also try a resistor/capacitor in parallel, in series with the gate, to try and even out the frequency response.  I am thinking 4.7 ohm & 4700pf.  I will also try 6.8 ohm & 4700pf.  Depends on how flat I can get the output.

Marco - KG5PRTÂ

On Jan 31, 2018 10:12 PM, "James Lawrie" <lawriejk@...> wrote:

Hello,

My shipment of replacement RF Mosfets have arrived and I want to replace the on board PASection with one based on the RD16HHF1. It will be a separate small PCB based on the reference design shown in the data sheet. I need help from the professionals here as to where to attach the new PA board.

I know it would be somewhere after the 2N2219A driver, and I want to remove all bypassed SMTs and or other parts from the Bitx board in that area. If you have a pretty good idea could you please let me know, and possibly a drawing if you could. This should keep me busy and off the forum for a while.

Slack chat client

Richard E Neese
 

Re: Replacing the PA section on Bitx 40

James Lawrie
 

My thought process is a separate board would allow more mounting options for a heat sink, and cleaner layout after on the Bitx 40. I hate to admit it but I’m not an engineer and even my basic math skills for electronics formula is severely restricted due to the “happy pills” I take for my service connected TBI and PTSD.

As a kid when I was trying to get into electronics and Ham I had a Elmer who helped, but now 41 years later I know no one else in my area who could/would help.I can follow schematics, and do basic - mid level troubleshooting, speaking of worse things I used to be very proficient in basic, pascal and early OOP programming, now thanks to my medical issues they are gone. I look a c and c++ and think it must be from Mars.

Probably TMI about myself but this is why I ask for help and like a clean board.

James Lawrie

Re: [SPAM] [BITX20] LTSpice simulation of uBitx Power Amp

K9HZ <bill@...>
 

Jerry… thanks for doing this.  I had intended to do this same thing but so many things kept getting in the way.  Since you uploaded the .asc I’ll try some of my favorite PA transistors in place of the 510s when I get back from vacation and see how they look.  The 3904s should be good above 50 mhz. also I suspect the stages are coupled a bit too tightly at higher frequency where something smaller would be more appropriate.  Anyway, nice work.

 

This does point out a few “oh yeah” things though.  The 510 miller cap loading at the higher frequencies is very high.  I guess you see that in the smith chart of the spec sheet too so no surprise.  Also, I think we see a lot of variation in the 510 parts…as some people report them working well at 20+ MHz and some not so much.

 

Yes agree.  I’d love to see a sim of the WA2EBY amp.  Dying to know the efficiency at 30 MHz.

 

 

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

 

 

email:  bill@...

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Jerry Gaffke via Groups.Io
Sent: Thursday, February 01, 2018 3:24 AM
To: BITX20@groups.io
Subject: [SPAM] [BITX20] LTSpice simulation of uBitx Power Amp

 

I've uploaded an LTSpice simulation of the uBitx Power Amplifier from Q90 on out through the IRF510's
but not including any of the transmit low pass filters, can be found here:
    https://groups.io/g/BITX20/files/KE7ER/ubitx_pa.asc
A pdf of the LTSpice schematic is here:
    https://groups.io/g/BITX20/files/KE7ER/ubitx_pa.pdf

I ran several simulations, all with a 0.05 volt pk-to-pk sine wave driven into C80 at the base of Q90.
Anything much higher and there was some definite gain compression going on.

With the IRF510 gates clipped out of the circuit, I saw 7.7v p-p of drive for each gate at 30mhz, 10.0v p-p at 7mhz.
Note that these signals were still loaded by the 47ohm resistors at R97 and R98

With the gates restored and the IRF510's powered from 12v, the gates had 3.0v p-p at 30mhz, 8.0v p-p at 7mhz.
Simulated power out (computed from the unfiltered p-p voltage into 50 ohms) was 5W at 7mhz and 0.9W at 30mhz. 
  
Will be interesting to see what this does if the gates are driven harder.
Also interesting to try a simulation of the WA2EBY amp using the same IRF510 models.

Jerry, KE7ER

Re: Nextion Display

Michael Monteith
 

Fred,
 Have you posted your work somewhere?  I bought a Nextion display over a year ago.  At the time the software was pretty messy.  I haven't touched it since.  But I would like to again.  Now I know who to bug if I have problems trying it again. lol  It would be great to have a professional looking display for the Bitx and uBitx systems.   I've got both to build at the moment.  Waiting on parts for one and pretty much spare time to work on the other.

73, Michael
KM4OLT

Re: Software support Request for Full QSK BITX40

Gary O'Neil
 

Thanks for doing the work generating the LTSpice file for the BITX40 PA. Saved me time and effort. I integrated my RF switch as it stands currently, and attaching it so you and others who might have the skillset to scrutinize and critique it. You're way ahead of me on the other emails, and it may be a fair amount of time before I get to them. I'm still peeling the onion on this switch at the moment, and don't want to divert my focus.

Tale a look at S21 in both transmit and receive. It looks great in Transmit mode, but receive insertion loss looks a wee bit high but not a show stopper. I also haven't taken a look at the before configuration yet, so it's not clear the switch is what's behind the insertion loss. By itself, the switch simulates (and measures) 0.2 dB insertion loss in receive.

Thanks again for doing the leg work on this... The integration was fast and easy. :-)

72/73

Gary, N3GO

Re: Slack chat client

David Arthur
 

Likewise, we have the Discord chat server setup. Link is in my sig. We have a record breaking 8 users active at the moment! :)

--
David K4DBZ
Unofficial bitx chatroom: https://discord.gg/CrHvWFc

Re: [SPAM] Re: [BITX20] Replacing the PA section on Bitx 40

 

Transmits fine Bill!

I have not experimented with correct bias setting but I was running more than 100 mils bias..
That board got displaced by the new toy uBitx.. I'll be back to it later later.


At 01/02/2018, you wrote:
Also… have you had it on the air like that yet?
 
 
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
 
 
email:  bill@...
 
From: BITX20@groups.io [ mailto:BITX20@groups.io] On Behalf Of Raj vu2zap
Sent: Thursday, February 01, 2018 4:24 AM
To: BITX20@groups.io
Subject: [SPAM] Re: [BITX20] Replacing the PA section on Bitx 40
 
Here is how I made the socket and mounted the RDD16

Note the RDD is reversed and  then the gate is actually soldered to the IRF gate line which goes behind the FET.
Now I can use either of them..

You will need to think of a heat sink plate that fits this way!

Emacs!

Case designed for uBITX - #3d_printing

Carl Beck
 

I designed a 3D printed Case especially for the uBITX.

Re: uBITX Firmware (CEC) 0.30 released (Test version). #ubitx

matjaz
 

hello,
i download source file ans compile.
In arduino recevied this mesage.
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino: In function 'void updateLine2Buffer(char)':
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino:150:32: warning: invalid conversion from 'byte* {aka unsigned char*}' to 'char*' [-fpermissive]
 
       strncat(line2Buffer, b, 5);
 
                                ^
 
In file included from C:\Program Files\Arduino\hardware\arduino\avr\cores\arduino/Arduino.h:25:0,
 
                 from sketch\ubitx_20.ino.cpp:1:
 
c:\program files\arduino\hardware\tools\avr\avr\include\string.h:422:14: note: initializing argument 1 of 'char* strncat(char*, const char*, size_t)'
 
extern char *strncat(char *, const char *, size_t);
 
              ^
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino:154:31: warning: invalid conversion from 'byte* {aka unsigned char*}' to 'const char*' [-fpermissive]
 
         printLine2(line2Buffer);   
 
                               ^
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_ui.ino:201:6: note: initializing argument 1 of 'void printLine2(const char*)'
 
void printLine2(const char *c){
 
      ^
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino: In function 'void idle_process()':
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino:223:31: warning: invalid conversion from 'byte* {aka unsigned char*}' to 'const char*' [-fpermissive]
 
         printLine2(line2Buffer);
 
                               ^
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_ui.ino:201:6: note: initializing argument 1 of 'void printLine2(const char*)'
 
void printLine2(const char *c){
 
      ^
What i am doing wrong.
73
Matjaz
 

From: Ian Lee
Sent: Wednesday, January 31, 2018 1:10 PM
Subject: Re: [BITX20] uBITX Firmware (CEC) 0.30 released (Test version). #ubitx
 
You can download source, compiled hex file, etc. from the link below.
 
How to upload Hex files can be found in my blog below.
 
Thanks for your interesting
 
Ian KD8CEC
 
2018-01-31 20:58 GMT+09:00 Kari Syrjänen <beaconhunter@...>:
Is there compiled version available somewhere?

Kari OH6YW
 

--
Best 73
KD8CEC / Ph.D ian lee
kd8cec@...
www.hamskey.com (my blog)

Re: Care and Feeding of SMD Parts

Tim Gorman
 

I've been working with these parts for several years. I take a piece of printer paper and slit the corners so I can fold it into a tray. The parts are easy to see against the white paper and the sides of the tray keep them from flying off into limbo. The tray is easy to move to wherever I am working making access easier. 

Re: uBITX Firmware (CEC) 0.30 released (Test version). #ubitx

Ian Lee
 

This is a warning that I am using byte and char without distinction.

If it does not compile and upload to ubitx, please wait a few days. I will remove warnings and release again.

I had a report from a beta tester using another compiler. Wait a moment and you will be able to download a clean source.

Thanks for information.

Ian kd8cec

2018. 2. 2. 오전 12:01에 "matjaz via Groups.Io" <matjaz_zejn=t-2.net@groups.io>님이 작성:

hello,
i download source file ans compile.
In arduino recevied this mesage.
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino: In function 'void updateLine2Buffer(char)':
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino:150:32: warning: invalid conversion from 'byte* {aka unsigned char*}' to 'char*' [-fpermissive]
 
       strncat(line2Buffer, b, 5);
 
                                ^
 
In file included from C:\Program Files\Arduino\hardware\arduino\avr\cores\arduino/Arduino.h:25:0,
 
                 from sketch\ubitx_20.ino.cpp:1:
 
c:\program files\arduino\hardware\tools\avr\avr\include\string.h:422:14: note: initializing argument 1 of 'char* strncat(char*, const char*, size_t)'
 
extern char *strncat(char *, const char *, size_t);
 
              ^
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino:154:31: warning: invalid conversion from 'byte* {aka unsigned char*}' to 'const char*' [-fpermissive]
 
         printLine2(line2Buffer);   
 
                               ^
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_ui.ino:201:6: note: initializing argument 1 of 'void printLine2(const char*)'
 
void printLine2(const char *c){
 
      ^
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino: In function 'void idle_process()':
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_idle.ino:223:31: warning: invalid conversion from 'byte* {aka unsigned char*}' to 'const char*' [-fpermissive]
 
         printLine2(line2Buffer);
 
                               ^
 
C:\ubitx\ubitx-0.33\ubitx_20\ubitx_ui.ino:201:6: note: initializing argument 1 of 'void printLine2(const char*)'
 
void printLine2(const char *c){
 
      ^
What i am doing wrong.
73
Matjaz
 
From: Ian Lee
Sent: Wednesday, January 31, 2018 1:10 PM
Subject: Re: [BITX20] uBITX Firmware (CEC) 0.30 released (Test version). #ubitx
 
You can download source, compiled hex file, etc. from the link below.
 
How to upload Hex files can be found in my blog below.
 
Thanks for your interesting
 
Ian KD8CEC
 
2018-01-31 20:58 GMT+09:00 Kari Syrjänen <beaconhunter@...>:
Is there compiled version available somewhere?

Kari OH6YW
 

--
Best 73
KD8CEC / Ph.D ian lee
kd8cec@...
www.hamskey.com (my blog)



--
Best 73
KD8CEC / Ph.D ian lee
kd8cec@...
www.hamskey.com (my blog)

Re: uBITX Firmware (CEC) 0.30 released (Test version). #ubitx

Ian Lee
 

Andrew

Thanks for using this firmware.

I will release v1.0 soon

Ian KD8CEC


2018. 2. 1. 오후 8:09에 "Andrew Farkas" <afarkas@...>님이 작성:

Very nice. I wish I could figure out FT-8. I can't get anyone to comeback on my regular rig. These apps are very intricicate. Too bad there isnt some kind of standard for making radio software work.

Andy

VA3AAF

On Feb 1, 2018 3:19 AM, Kari Syrjänen <beaconhunter@...> wrote:
Ian's firmwares working great! I have been using then since version 0.25

Now running 0.33 and working 7MHz FT8-mode. Over 350 QSO.s in my logbook

TNX!

Kari OH5YW



--
Best 73
KD8CEC / Ph.D ian lee
kd8cec@...
www.hamskey.com (my blog)

Re: Care and Feeding of SMD Parts

Don WB4AFP
 

I have been using a 3-ring binder with clear plastic pages meant to hold trading cards -- 9 to a page.  The little strips go into the pockets quite nicely.  This also works pretty well for thru-hole resistors and caps.  With loose parts in the pockets it does take a little care leafing thru the pages not to spill the parts.

I label the pockets using a small permanent marker on the window, and a very fine marker on the back of the strips.

Chip resistors tend to be marked with part values, which can be read under a low-power microscope.  Capacitors tend not to have any markings.  I guess that there are so many things you need to know about a capacitor, like what ceramic, and the voltage rating, that you would need an electron microscope to read it.  The only markings are on the reels the tapes come on.

Industrially, these things are handled only as full reels, which are put into the pick-and-place machine AKA "chip shooter".  Individual markings on the parts themselves would be redundant.