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Re: ubitx compared to Elecraft or Xiegu for spurs #ubitx

Jim Myers
 

Comparing a multi-thousand dollar commercial radio product to the uBITX is silly.
Re: #bitx40help BITX40 LSB Winlink #bitx40help

 

First the code (Arduino sketch)had to be changes to set the 5351 to the needed range for 20M.
That is both the LO and the BFO as needed.? You will need the 40M sketch to do that.

The 40M band pass filter gets changed to 20M, Look for the schematic of the older bitx20
series for values.

Then the 40M low pass filter needs to be changed.

Ignore any noise about changing the IRF510s.? I have run those to over 70mhz at?
high power (20W at 13.8V).? ?Its a competent enough device assuming the circuit
around it is correct.

>>The magic is in the ladder/BFO combination, which shears off the carrier and unwanted sideband, while passing the wanted sideband.??

Only half true.? The balanced modulator is to remove the carrier, the filter passes the desired
sideband (strips the other).

Allison
Re: ubitx compared to Elecraft or Xiegu for spurs #ubitx

 

>>>I had a quick look at my KX3 on the specan and its really clean.? Will have to do better test when I get?some ?time :)
73's VK5ZBR

Over the years I have had the chance to check out most all of the Elecraft lineup.
For pit FD site the are the preferred radio for being clean (all models).? The look
good on bandscopes.? The acid test is two of them on the same band running
phone and CW and not having mutual interference.

That and look at the specs.

Allison
Re: Spurious Emission Measurement on stock uBitX

 

Iz oos, Arv, and all...

That test was CW mode so harmonics would be the prime issue.? It is required
to be SSB? for the spurs (and harmonics) to appear.? Its the difference between
how one is done CW is direct Frequency against the other SSB which is converted
fro 45mhz to the signal frequency.

If you do not keep track of the mode you will run off lost into the weeds.

Allison
Re: #bitx40help BITX40 LSB Winlink #bitx40help

Timothy Fidler
 

JM there is a whole lot of information here around this BBS in various corners.? see right down bottom of this post...
(public version of post sent privately a while back)?
Extra filters can come from Kees Talen who sells little PCBs for this purpose .? Moto appn note AN267 is? your friend for this design.? KT sells parts .. you do the design.

you will need to change out the IRF PA for a? proper Mitsi HF or VHF Mosfet. The pinouts don.'t align as Flowers found out but he worked out a kludge - eg wiring the RF transformer direct to the drain of the RDHH16.? The fact that the? Source and tab on the RDHH16 and 15 Mosfets are the same simplifies some of the rework and of course makes heat sinking a lot easier. Those Mosfets are avail at reasonable prices as in just over 5 usd plus freight from "cecil the parts place". DIZ,? the toroid king used to stock them but >....no more.

? There is a V2 version two that involves?hardware mods- BEWARE.??Best have a backup plan like a second Raduino or a clone so you can always fall back to plan A.
?
? ?is a new load of software that may do many things you want. It also contains a whole lot of fixes and includes CW capability.

In terms of display for both 40 and 20 m with a dual band design (??)? this item (search for 6 digit freq counter) from??might solve your problem $13 USD without a recode job. you use the frequency counter in native mode to display frequency in 20m operation and the original Bitx display for 40 m operation? (sounded like a good idea at the time ).

Type 43 material is pretty lossy above? 7 Mhz.(can forward data) there are magnetics which if you change? them out will make a difference.? ?Flowers got 6W out he says with only the Mosfet change.? Without that change he was getting less than 2 W out.

MOtorola design note AN267 is your friend for? designing the New output filter.? (Kees supplies parts not designs)
===============================================================================
With six watts you can drive plenty of amps that will give you 50W+? out?



Just The guts of this amp come up from time to time on Ebay as just PCBs all ready to go but no case? for region of $80 USD. It uses an MRF-186 dual RF mosfet? ..beware imitations esp beware of SMPS mosfet kits .? Crude as hell but it works and is hard to kill it seems. Somebody in PRC obviously lucked into a whole lot of surplus Motorola parts at bargain prices

There are some reviews of it on Austr. websites./blogsites?
======================================================================================

/g/BITX20/topic/bitx40_convert_to_20_meters/5162026?p=,,,20,0,0,0::recentpostdate%2Fsticky,,,20,2,0,5162026
Re: Ubitx - Increased voltage to finals thru middle wire on power plug...no effect

Kevin Rea
 

Hi Adrian,
is there a current limit somewhere in the rig?

Kevin Rea
Re: Ubitx - Increased voltage to finals thru middle wire on power plug...no effect

Kevin Rea
 

hi Adrian, no I do not have any current limiting that I know of I'm powering the 12 volts with 5 amp and then I'm powering the sitter lead of the power connector with a 5 amp at 23 volts and I am getting 23 volts at the finals. Still ,no difference in output.
Re: #ubitx SSM2167 mic compressor speaker feedback issue - resolved #ubitx

 

Thanks Kevin.

Tim, I didn't write down the results but I remember noting that the average power was more than twice as without the compressor.

73, John
Re: Spurious Emission Measurement on stock uBitX

 

Looking at the ¡°strongest spur frequency¡± column, 42.4700MHz spur was -41.1dBc at 21.2250MHz row.

However, with AT, the 42.4700 spur was dropped to only -45.6dBc which tendency is different from other bands.

Then looking at the 28.8500MHz rows, 14.4270MHz spur was observed as the strongest without AT, but 43.3000MHz was the strongest spur with AT.

Maybe this Pi-C AT does not work efficiently above 30++MHz?

I don¡¯t know. So additional LFP which cuts above 30MHz may be a good trial.

I¡¯ll do it next time, maybe after casing my uBitX.

// hiro, JJ1FXF



2018Äê8ÔÂ18ÈÕ(ÍÁ) 5:21 iz oos <and2oosiz2@...>:

Arv,
I said that on the basis of the results shown in the table by Hiro. At 15m he has shown the biggest spur at 42Mhz not the one Allison first detected on 23Mhz. For the one at 42Mhz a CB low pass should suffice.


Il 17/ago/2018 20:13, "Arv Evans" <arvid.evans@...> ha scritto:
Iz Oos

Might not want to encourage uBITX users to expect that a CB filter will make it legal
on 15 meters.? The 15M spur is in the 23 MHz range so would not be attenuated by
a 30 MHz LPF.

Arv K7HKL
_._


On Fri, Aug 17, 2018 at 9:31 AM iz oos <and2oosiz2@...> wrote:

Hi Hiro, nice analysis, if I understand right if you add also any 30mhz (also like CB) lowpass filter you may transmit on 15m band. Isn't? Is the Trio tuner a simple pi-tuner? I have just done a variable low pass filter with a double 450pf air variable capacitor a six position switch and a 130-7 toroid and looking at PC the results from my antenna analyzer it seems better than expected.


Il 17/ago/2018 16:39, "JJ1FXF" <jj1fxf@...> ha scritto:
Hi, all.

Attached is a PDF file which shows the results of measuing spurious emission on my uBitX which I haven't modified its hardware/software at all.

Here, in Japan, the spurious emission should be less than -50dBc and so the list indicates I can use my uBitX with a Pi-C antenna tuner, but not on 15m unfortunately.

This time, I checked only the CW transmission beccause I had a problem to measure SSB case. It would be very much appreciated if someone could advise to me.

To measure the spurious emission on SSB, at first I need to saturate the PA output by the mic input of so called "pseudo voice" that is 1.5kHz sine wave, and when the output is saturated by increasing the input leve, then 80% of the input level will be used to measuer spurious emission, the Lab guy explained to me.

However, uBitX output won't be saturated which means I couldn't observe the flat level of PA output as increasing the input (pseudo voice) level, but suddenly the output level falls down to a few mW.

The Lab guy said it would be because uBitX didn't have an ALC - Auto Level Controller of the mic input.

So please advise to me how I can saturate the output (PA) level with such a "pseudo voice" input? Maybe bring an external mic compressor? However, how can I observe the flat level of PA output?

Thank you for reading my long email. Hope someone can help me. If you are interested in screen shots of the spurious analyzer, feel free to email me.

BR,

// hiro, JJ1FXF
Re: #ubitx SSM2167 mic compressor speaker feedback issue - resolved #ubitx

Timothy Fidler
 

That is just beautiful . Has anyone measured the improvement in PEP out with compression on ??
Re: #bitx40help BITX40 LSB Winlink #bitx40help

Jack Margolis
 

I'm still confused on how to change the frequency of the Radiuno that is supplied with the Bitx40 kit.

Does one need to edit the sketch of push buttons on the Radiuno.? I've looked at the firmware and it shows the bottom and top range of the two VFOs.? ?

I am also not sure about setting the BFOs, etc to give me USB on 20 Meters.? I want to buy a 40 meter Bitsx change the two filters ....then do whatever to the Raduino.

Thanks in advance for your help.? ?73? ?Jack??
Re: Spurious Emission Measurement on stock uBitX

 

Allison san,

Thanks for your info. I tried some apps from Apple Store and seemed any of them might be OK.

I will plot the PA output level as increasing the volume of iPhone.

// hiro, JJ1FXF



2018Äê8ÔÂ18ÈÕ(ÍÁ) 2:59 ajparent1/KB1GMX <kb1gmx@...>:

Hiro san,

To do testing on SSB a audio tone signal source is needed. There are aps for android
and Iphone that do this.? The procedure is generate the 1.5khz tone and inject it into
the microphone input.? Turn audio source volume up until power does not increase
then reduce to the specified 80% of max power for each band.? Repeat this on a
per band basis for best results.? Note power out used for that band.


Allison
Re: #ubitx. Increasing power output

Timothy Fidler
 

bsx 20 this time

BSX20Data.pdf
BSX20Data.pdf

Re: #ubitx. Increasing power output

Timothy Fidler
 

I have not got one to play with but the? BSX-20s work better on small signals than 2N2222 because of lower input capacitance and have no VHF roll off? until well above? 300 Mhz - pull up? a datasheet.? Futurelec.com list them but say no stock. Send Futurlec and email .. often they can find stuff? . BEWARE the 15V VCE max.? Beware destroying the PAs Too. Beware the small size of the output transformer on the PAs .? there should be a D sheet uploading with this post for the BSX
Re: N6ALT: Nextion 3.2 inch Enhanced display not displaying right

 

Hi Joe,

Thanks for the tip, it worked great.

Joel
N6ALT
Re: second arduino Smeter firmware

MD
 



--
N5KBP
Re: Raduino Clone kit from W0EB-N5IB #ubitx

V Zecchinelli
 

¿ªÔÆÌåÓý

Got it.? Thank you sir.

Vince, N1VIN



On 8/17/2018 3:47 PM, Paul KL7FLR wrote:

The Raduino¡¯s used with the uBITX and BITX40 are identical with one exception, the 16 pin P3 connector. The uBitx used a 16 pin right angle header to plug into the main board.? The BITX40 uses a 5 pin molex style connector? at pins 12 thru 16 of P3.

Starting with a bare board you have your choice of which connector to use for the appropriate radio. Totally interchangeable with the one exception.

?

Paul

KL7FLR

?
second arduino Smeter firmware

 

Hi All:
After long hiatus from the ubitx, I purchased a 3.5 Nextion LCD works great! I am using KD8CEC second arduino for the S meter, the circuit is built ready to go, however I can't program the arduino until I can find the program .Probably looking in the wrong place, if someone could to steer to me location would be appreciated.
Thanks Ross Bell K7RSB
Re: Spurious Emission Measurement on stock uBitX

 

Arv,
I said that on the basis of the results shown in the table by Hiro. At 15m he has shown the biggest spur at 42Mhz not the one Allison first detected on 23Mhz. For the one at 42Mhz a CB low pass should suffice.


Il 17/ago/2018 20:13, "Arv Evans" <arvid.evans@...> ha scritto:
Iz Oos

Might not want to encourage uBITX users to expect that a CB filter will make it legal
on 15 meters.? The 15M spur is in the 23 MHz range so would not be attenuated by
a 30 MHz LPF.

Arv K7HKL
_._


On Fri, Aug 17, 2018 at 9:31 AM iz oos <and2oosiz2@...> wrote:

Hi Hiro, nice analysis, if I understand right if you add also any 30mhz (also like CB) lowpass filter you may transmit on 15m band. Isn't? Is the Trio tuner a simple pi-tuner? I have just done a variable low pass filter with a double 450pf air variable capacitor a six position switch and a 130-7 toroid and looking at PC the results from my antenna analyzer it seems better than expected.


Il 17/ago/2018 16:39, "JJ1FXF" <jj1fxf@...> ha scritto:
Hi, all.

Attached is a PDF file which shows the results of measuing spurious emission on my uBitX which I haven't modified its hardware/software at all.

Here, in Japan, the spurious emission should be less than -50dBc and so the list indicates I can use my uBitX with a Pi-C antenna tuner, but not on 15m unfortunately.

This time, I checked only the CW transmission beccause I had a problem to measure SSB case. It would be very much appreciated if someone could advise to me.

To measure the spurious emission on SSB, at first I need to saturate the PA output by the mic input of so called "pseudo voice" that is 1.5kHz sine wave, and when the output is saturated by increasing the input leve, then 80% of the input level will be used to measuer spurious emission, the Lab guy explained to me.

However, uBitX output won't be saturated which means I couldn't observe the flat level of PA output as increasing the input (pseudo voice) level, but suddenly the output level falls down to a few mW.

The Lab guy said it would be because uBitX didn't have an ALC - Auto Level Controller of the mic input.

So please advise to me how I can saturate the output (PA) level with such a "pseudo voice" input? Maybe bring an external mic compressor? However, how can I observe the flat level of PA output?

Thank you for reading my long email. Hope someone can help me. If you are interested in screen shots of the spurious analyzer, feel free to email me.

BR,

// hiro, JJ1FXF
Re: #ubitx SSM2167 mic compressor speaker feedback issue - resolved #ubitx

Kevin Rea
 

i put it on my website.. it is a larger image if anyone needs one.
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