Date   

Re: ?- How high SWR before smoke? - 6146

David <k6dma@...>
 

Yes, tubes can be spectacular.


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

ajparent1/KB1GMX <kb1gmx@...>
 

Giles,

Before every hijacks the topic which is focused on using crystal filters
in a dual frequency IF.

I don't have that SOTA filter.  I build CW radios with narrow crystal filters or in the case of
analog I/Q phasing use analog filters of the desired bandwidth.   Though I usually
add a stage of active filter in the design to reduce high frequency hiss even to
SSB radios.

Any of the switched capacitor filters are good and there is software suitable for a faster micro
like Rpi or the STFx series to do it digitally.  Just create another topic for that and not disrupt
this one.

Allison


Re: History of ubitx versions #ubitx

FC
 

Thank you all for the additional information.


Re: History of ubitx versions #ubitx

ajparent1/KB1GMX <kb1gmx@...>
 

Yes, V1 was LC filter.  V2 ws 45mhz and also increased the number of low pass filters.

The design has not changed significantly. since V2.

Allison


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

iz oos
 

Adding another IF narrower filter might be the best solution. However some may be almost equally satisfied adding a good audio filter. Good receivers by Lowe had 200hz wide audio filters for CW. I have tried the hi-per-mite filter by SQRP and is a great filter one could connect at the speaker output or I believe before the audio final as the filter can provide audio gain depending on the settings.


Il 07/lug/2018 18:45, "Gilles Delpech" <gilles.f1bfu@...> ha scritto:
Hi Allison

Use sota beams audio filter with an additionnal amplifier (LM386 for example° ?
I have a uBitx V3 and a Sota Beams audio filter on wait. 
How you have connect the audio filter ? On the HP of uBitx or on the headphones connector ?

73 Gilles F1BFU / FR

 

2018-07-07 18:23 GMT+02:00 Dave Dixon <wylyeguy2@...>:
I am using a sota beams audio filter on my version 3 u bitx and it works brilliantly. Dave G0AYD.

On 7 July 2018 at 12:17, ajparent1/KB1GMX <kb1gmx@...> wrote:
Jerry that pointer is to bitx 40/20 tuning clicks.  The Sotabeams audio filter was
mentioned and I know that would work well.

Allison




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

Joe
 

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


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

ajparent1/KB1GMX <kb1gmx@...>
 

When and if you get it to work please post your results and what it took to make it work.

Yes the ports are 50 ohms, that's never been secret but if you have two 50 ohm devices
(source and load) and then parallel a third 50 ohms device what is that, not 50 ohms.
Only the IF and the Balanced mod are 50 ohms, the filter is 50 ohms in the band pass and
whatever outside it.  

I never said the idea to switching IF frequency will not work. ONly paralleling filter will not work well
due to one more or less shorting out the other.  You have already written that part up.  I did expllain
those of us that can design would do it and it would work well.  Also every stinking cheap am/fm
radio has a dual frequency if both 455 and 10.7 and thats been done for over 50 years.
Been in engineering or over 50 years, my specialty is making the won't work things,  work.
But that unusually means some fancy design or understand how it works to start with.

Two things.   I told you how to do it and it will work if you do that.   I said your hack
of paralleling them relies on things that will be guaranteed to work poorly unless lucky.
Also Farhan said 1.842mhz filter and you didn't try that.  

Now your own words:
>>>The idea of switching the IF frequency to switch filters appears to be sound - just need to find the magic crystal/capacitor/transformer combination and for that I need someone with better knowledge of crystal filters and better test equipment that I have.<<<
I have both and your proceed to disagree.  
Until other post their work it is vaporware.  I have your posting it didn't work.

>>>>So far I've not been able to get a signal through filters at 4.6,  6.2 or 8 MHz.<<<<

You didn't try 1.8432, and you did get some signal but the attenuation is high.  
Silly question did you try the filter without the 12mhz filter shorting it?  That
would prove your filter works.  You could also do that using a bench jig.
You only need signal generator and a scope maybe a few resistors to simulate
a 50 ohm load.

Me I'd mod the 12mz and make it a jones filter (varicap tuned variable bandwidth)
as used in some older Tentec and the Elecraft K2.   I like that as it means the board
only needs parts added (varicap diodes and resistors to a control point) and no
hacking it up.  It is an old idea and discussed before.


Allison


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

F1BFU - Fr - 79
 

Hi Allison

Use sota beams audio filter with an additionnal amplifier (LM386 for example° ?
I have a uBitx V3 and a Sota Beams audio filter on wait. 
How you have connect the audio filter ? On the HP of uBitx or on the headphones connector ?

73 Gilles F1BFU / FR

 

2018-07-07 18:23 GMT+02:00 Dave Dixon <wylyeguy2@...>:

I am using a sota beams audio filter on my version 3 u bitx and it works brilliantly. Dave G0AYD.

On 7 July 2018 at 12:17, ajparent1/KB1GMX <kb1gmx@...> wrote:
Jerry that pointer is to bitx 40/20 tuning clicks.  The Sotabeams audio filter was
mentioned and I know that would work well.

Allison




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

Dave Dixon
 

I am using a sota beams audio filter on my version 3 u bitx and it works brilliantly. Dave G0AYD.

On 7 July 2018 at 12:17, ajparent1/KB1GMX <kb1gmx@...> wrote:
Jerry that pointer is to bitx 40/20 tuning clicks.  The Sotabeams audio filter was
mentioned and I know that would work well.

Allison



Re: HEX files with Mac OS

Mark M
 

Thanks for the pointers, Tom. I'll check them out.

73.... Mark AA7TA

On 7/6/18 10:27 PM, Tom, wb6b wrote:
I did a Google search looking for something that might be promising. I stumbled upon this.
Have not tried it and it looks like it is old. However, that could mean it is out of date, or it is perfect and has never needed any bug fixes or updates.
http://www.w7ay.net/site/Applications/AVR%20Tools/index.html
Tom, wb6b


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

Jerry Gaffke
 

Post 48530 is with regard to a uBitx.
No mention of sotabeams anywhere in the thread.
It includes the following statement
"During the tuning process, at every frequency change, the function was called
and set the correct  IF oscillator frequency to 4Mhz or 12Mhz (dependant on wide or narrow)."

That was the cause of his clicks.
And that sounds to me like two crystal filters at 4 and 12 mhz,
he would have to move the BFO when selecting the other filter (also move clk1).
I followed up with a post for clarification as it is not very clear,
but there was no further response.

I can believe it does not work terribly well.
But could be worth trying, or at least worth modeling the impedances of
the unused filter.
Farhan's original selection of 12.0 and 1.8432 mhz would place the filters
very far apart, that might help.

Jerry


On Sat, Jul 7, 2018 at 04:17 am, ajparent1/KB1GMX wrote:
Jerry that pointer is to bitx 40/20 tuning clicks.  The Sotabeams audio filter was
mentioned and I know that would work well.


Re: NEXTION DISPLAY UPDATES For KD8CEC ver 1.094 up

Bo Barry <wn4ghv@...>
 

The enhanced version allows addition of the little expansion board which will allow extra push button modes, among other things. Handy.
Bo W4GHV 


Re: Perfect pop and click fix for CW only operators

Tom Cooper
 

UBITX V3 is what I have.


Re: Completed my QCX #ubitx

pat griffin
 

Thanks so much. Just the data I need. 
73
Pat aa4pg

On Jul 6, 2018, at 10:44 PM, Ralph Mowery <rmowery42@...> wrote:

Pat here is some of what I measured when using a service monitor.

Voltage DC across C4.

4 volts was the maximum with -40 dbm input to the antenna connector.
3.9 V -50 dbm
1.8 V -60 dbm
.55 at -70
.1 V at -80 dbm
.03 at - 90 dbm

.4 V at -73 dbm which is 50 uV , the socalled s-9 signal .


Using the 2 line by 16 charicter display I adjusted the display so tht 50 uV shows up as 3 bars.
6 bars is -63 dbm. One + is -57 dbm and two ++ is -51 dbm.
That seems to make the meter show up for me using an off center fed dipole on 80 and 40 meters.

73 de ku4pt



On Fri, Jul 6, 2018 at 8:10 PM, pat griffin <patgriffin@...> wrote:

Ralph,

Can you tell what voltage levels you are seeing there? On a strong signal I see about .4VDC across C4 of the AGC circuit.

Thanks,

Pat AA4PG



From: BITX20@groups.io <BITX20@groups.io> on behalf of Ralph Mowery <rmowery42@...>
Sent: Thursday, July 5, 2018 9:20:55 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Completed my QCX #ubitx
 
If you install the AGC kit you can just use it for the S-meter.  Just tap off the first pin where the several jumper pins are for the delay. Works fine.


On Thu, Jul 5, 2018 at 9:48 PM, WD8WV <juddie.d.burgess@...> wrote:
Pat,

I haven't built the S-Meter circuit yet.  I had it turned on but it really isn't doing anything, don't know why sometimes I see what appears to be signal since there is no circuit in it yet.  I have to order the LM358 chip, everything else I have.  I was going to do the circuit with the LM386, which I have 3 of those from where I was building Pixie kits.  I bought several and have 3 new ones left.  Dr Lee, KD8CEC texted me on his blog that it would be better to use the LM358 chip.  I just received in the mail the TX/RX pop fix kit and the AGC kit that I read about.  Of course I have never done SM soldering, so don't know if I will be able to do this.
--
Judd, WD8WV



Re: History of ubitx versions #ubitx

Lawrence Galea
 

The original used an LC 45 MHz band pass filter and part of the TDA2282 as an AGC system together with a mosfet.
Then both the LC 45 MHz BPF and the AGC system were dropped and a crystal filter was used instead of the 45MHz LC filter (V3).
V4 uses a different AF amplifier and other changes.




On Sat, Jul 7, 2018 at 8:48 AM, Mike Woods <mhwoods@...> wrote:
There are two versions of the kit:  v3 and v4.   The v4 board has been included in kits for about the last 6 weeks.  The earlier v3 board was released 7 December 2017.  There were some differences in component brands on the v3 board reflecting sourcing difficulties experienced by the manufacturer.  In particular,the TDA2822 audio chip had three variants, with the middle variant having issues with self-combustion.  The manufacturer estimated around 165 boards were affected.  

I suspect that v1 and v2 were prototype boards only. 

There are not that many differences between v3 and v4 boards and software and all peripheral components are compatible.   The primary differences being the addition of any audio anti-pop circuit(5 additional parts), the replacement of the TDA2822 with an audio amp made of discrete components.   There are other minor changes including the addition of test points throughout the board to make it easier to make modifications to the board.

Hope this helps.

Mike ZL1AXG ubitx.net

On Sat, 7 Jul 2018 at 3:58 PM, - <felix@...> wrote:
I see that the ubitx is currently at version 4 and I'm trying to gauge how fast it's being revised and the reasons for it. Is there a list showing the date and changes or reason for each version?



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

Jim Sheldon
 

Guys,
I know I stirred up a can of worms with this topic, but I already have the NESCAF audio filters in all of the uBITX rigs (5) that I've built.  However, Ashhar DID say (I have an email from him telling me the I/O impedance for those header connections was 50 ohms and Alex, PA1FOX apparently has made it work like Ashhar intended.  All I was trying to do is get information on anyone having successfully accomplished this, not a bunch of engineering theory on why it won't work.  

If Allison had read Alex's (PA1FOX) a bit more closely she'd see his reference to switching IF frequencies to switch filters.  His click problem was created by the way he originally handled the firmware for shifting the IF to the new filter frequency - he was doing it far more often than necessary and that was creating the clicks.

That part of the problem has been solved.  

I'm not an engineer but I am a good technician and taught electronics for the US Army Security Agency at Fort Devens, MA for a number of years between 1968 and 1981 when I retired.

My major problem is I'm not afraid to test something that isn't supposed to work and see if there is a solution to why it won't work or prove the nay sayers wrong.  You guys are so busy picking apart the idea and using theory to "prove" it can't work.  I'm trying to prove you wrong - LOL.

Let's just agree to disagree on this particular subject and see what Alex, PA1FOX has to say if he answers my private email to him requesting further info.

5 MHz isn't a good selection though as the 9th harmonic of 5 falls in the 45 MHz first IF range and someone also posted on huge birdies caused by that selection (Ashhar had suggested 5 MHz as a possibility in one of his very early posts on the V4 boards).

Jim Sheldon

------ Original Message ------
From: "ajparent1/KB1GMX" <kb1gmx@...>
Sent: 7/7/2018 6:17:06 AM
Subject: Re: [BITX20] Crystal CW filter with Version 4 uBITX boards? #ubitx

Jerry that pointer is to bitx 40/20 tuning clicks.  The Sotabeams audio filter was
mentioned and I know that would work well.

Allison


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

ajparent1/KB1GMX <kb1gmx@...>
 

Jerry that pointer is to bitx 40/20 tuning clicks.  The Sotabeams audio filter was
mentioned and I know that would work well.

Allison


Re: History of ubitx versions #ubitx

Mike Woods
 

There are two versions of the kit:  v3 and v4.   The v4 board has been included in kits for about the last 6 weeks.  The earlier v3 board was released 7 December 2017.  There were some differences in component brands on the v3 board reflecting sourcing difficulties experienced by the manufacturer.  In particular,the TDA2822 audio chip had three variants, with the middle variant having issues with self-combustion.  The manufacturer estimated around 165 boards were affected.  

I suspect that v1 and v2 were prototype boards only. 

There are not that many differences between v3 and v4 boards and software and all peripheral components are compatible.   The primary differences being the addition of any audio anti-pop circuit(5 additional parts), the replacement of the TDA2822 with an audio amp made of discrete components.   There are other minor changes including the addition of test points throughout the board to make it easier to make modifications to the board.

Hope this helps.

Mike ZL1AXG ubitx.net

On Sat, 7 Jul 2018 at 3:58 PM, - <felix@...> wrote:
I see that the ubitx is currently at version 4 and I'm trying to gauge how fast it's being revised and the reasons for it. Is there a list showing the date and changes or reason for each version?


Re: HEX files with Mac OS

Frank PA7F
 

Bill,

Do a search for 'xloader for mac' on this list. Somebody found one not too long ago.

Frank PA7F


Re: HEX files with Mac OS

Tom, wb6b
 

I did a Google search looking for something that might be promising. I stumbled upon this.

Have not tried it and it looks like it is old. However, that could mean it is out of date, or it is perfect and has never needed any bug fixes or updates.

http://www.w7ay.net/site/Applications/AVR%20Tools/index.html

Tom, wb6b