Date   
Re: Cool cheap oscilloscope for troubleshooting

Jerry Gaffke
 

For those starting out, I'd start with a cheap DVM (ideally one that measures
capacitance too) and perhaps one of those JYE oscilloscopes.
Build some audio amps up from transistors, look at how they work with the scope.
Calibrate it by looking at a the 5v square wave coming out of the si5351 on the Raduino
(the si5351 can be made to go down to 4khz, or you could use a Nano counter/timer).
Write code to set that square wave to any frequency you want, and perhaps sweep through a range
of frequencies.  .Scale that square wave amplitude using resistors and verify the result on the scope.
Try building some of your own test gear, perhaps a diode RF probe for the DVM, and a step attenuator.
Use the Raduino as a signal source to evaluate the response of a filter or amplifier.
All of the above could be done for around $100, including the $59 cost of a Bitx40 and the $20 JYE scope.

Farhan is probably right, something like the Antuino is perhaps more useful than a scope
for radio work.  Though I'd find it hard to get by without a scope of some sort.
The scope helps us visualize what is really going on.

For those not starting out, you probably already know if it's worth kilobucks to you
for high end scopes and spectrum analyzers and binocular inspection microscopes
and vector network analyzers and signal generators and frequency counters and
rubidium standards and current limiting power supplies and desoldering stations
and a building out back to put it in.

Jerry, KE7ER


On Wed, Jul 31, 2019 at 11:51 AM, Doug Hall wrote:
Jack's point is well made. I'm all for saving money, but of all the places to cut corners test equipment is not one of them. The biggest flaw in the $25-$50 'scopes is not their lack of features or low bandwidth, it is their lack of measurement accuracy. And when you think about it, measurement accuracy is the reason we buy test equipment in the first place. 

You can buy a new Rigol DS1102E for $300. That's a dual channel 1 gigasample per second, 100 MHz bandwidth 'scope with two decent X10 probes and a host of features such as FFT (use it as a spectrum analyzer), PC connectivity, USB, on-screen help, and math features. Talk your club or a few of your buddies into going in with you if you can't justify $300. But a decent oscilloscope is worth what you pay for it. 

Speaking of Rigol equipment, several years ago I saved my toy money and bought a Rigol DSA-815 spectrum analyzer with a tracking generator. For the money you can't beat it. Besides measuring stuff like spectral purity and TX IMD3 you can also measure filters and tune duplexers, check coaxial cable loss, and a host of other things. 

Re: CLKn frequencies for uBITx v5

 

This page will help Ravi, the block diagram is clear:

http://www.hfsignals.com/index.php/ubitx-circuit-description/

I have taken the uBitxs off my table and poking into the antuino for now.


Raj

At 31-07-19, you wrote:
Hi,

I'm still trying to understand how the frequencies (3 of them)
interact and produce the final output.

Could I ask if some of you could send the frequencies (preferably
nn.nnnnnn) of CLK0, CLK1 and CLK2 for 14MHz (USB) and 7MHz(LSB) so
that I can compare the ones generated by my set.

I understand that the BFO may differ due to the characteristics of the
QER filter, but I can make allowances for that.

What do others think?

Kind regards,

Ravi/M0RVI

Re: Ver 5.1 uBITZ Calibration

MVS Sarma
 

It needs to have a frequency counter.for calibration at 10mhz.
 Perhaps you can pretue a q0mhz wwv on any other radio and in close vicinity you try calibration trying to hear a beat.

A link to detaild procedure i shall send soon, please.

On Tue, 30 Jul 2019, 12:34 am Liam Kingsmill, <lumetters1@...> wrote:
Sarma, stock firmare here.

Re: FS: QRP Gear

iz oos
 

As it was QRP stuff I didn't find inappropriate. If it had been the selling of ordinary flashing brand stuff I would have simply considered it as spam.


Il 31/lug/2019 19:08, "N8DAH" <Dherron@...> ha scritto:

I would but having done that in the past with other items didn't work. I have found selling them via qrz works better then the hope someone will stumble on them on my store front. Most people come to my site for the AGC and other bitx items.

Again I had to move the items quickly and posting here and on other qrp groups got the job done.
--
David

 N8DAH
Kit-Projects.com

Shop is open!

ubitx with Icom SM-6 desk mic

John Scherer
 

I've got an Icom SM-6 desk mic sitting around and I'd love to wire this up to my ubitx v5.  Its clear that this mic has its own preamp and I'm not certain if I need to make any changes for this mic to work.

http://www.radiomanual.info/schemi/ICOM_ACC/Icom_SM-6_user.pdf

--
John - N0CTL - Fulltime RV in a 40' motorhome

Re: Cool cheap oscilloscope for troubleshooting

David Wilcox
 

Has anyone information on how to use the Digilent analog scope?  The reference manual reads like a college text book on its features but using it for ham radio testing for a newbie I need a simple book  with lots of pictures..... ha!

David J. Wilcox K8WPE’s iPad

On Jul 31, 2019, at 11:36 PM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

For those starting out, I'd start with a cheap DVM (ideally one that measures
capacitance too) and perhaps one of those JYE oscilloscopes.
Build some audio amps up from transistors, look at how they work with the scope.
Calibrate it by looking at a the 5v square wave coming out of the si5351 on the Raduino
(the si5351 can be made to go down to 4khz, or you could use a Nano counter/timer).
Write code to set that square wave to any frequency you want, and perhaps sweep through a range
of frequencies.  .Scale that square wave amplitude using resistors and verify the result on the scope.
Try building some of your own test gear, perhaps a diode RF probe for the DVM, and a step attenuator.
Use the Raduino as a signal source to evaluate the response of a filter or amplifier.
All of the above could be done for around $100, including the $59 cost of a Bitx40 and the $20 JYE scope.

Farhan is probably right, something like the Antuino is perhaps more useful than a scope
for radio work.  Though I'd find it hard to get by without a scope of some sort.
The scope helps us visualize what is really going on.

For those not starting out, you probably already know if it's worth kilobucks to you
for high end scopes and spectrum analyzers and binocular inspection microscopes
and vector network analyzers and signal generators and frequency counters and
rubidium standards and current limiting power supplies and desoldering stations
and a building out back to put it in.

Jerry, KE7ER

On Wed, Jul 31, 2019 at 11:51 AM, Doug Hall wrote:
Jack's point is well made. I'm all for saving money, but of all the places to cut corners test equipment is not one of them. The biggest flaw in the $25-$50 'scopes is not their lack of features or low bandwidth, it is their lack of measurement accuracy. And when you think about it, measurement accuracy is the reason we buy test equipment in the first place. 

You can buy a new Rigol DS1102E for $300. That's a dual channel 1 gigasample per second, 100 MHz bandwidth 'scope with two decent X10 probes and a host of features such as FFT (use it as a spectrum analyzer), PC connectivity, USB, on-screen help, and math features. Talk your club or a few of your buddies into going in with you if you can't justify $300. But a decent oscilloscope is worth what you pay for it. 

Speaking of Rigol equipment, several years ago I saved my toy money and bought a Rigol DSA-815 spectrum analyzer with a tracking generator. For the money you can't beat it. Besides measuring stuff like spectral purity and TX IMD3 you can also measure filters and tune duplexers, check coaxial cable loss, and a host of other things. 

Re: Cool cheap oscilloscope for troubleshooting

Tom, wb6b
 

Someone told me they saw an old Tektronix 465 scope on eBay for $50 (probably $150 shipping :) ). That could be a good route. Hard to imaging that those scope might have cost $20,000 or more in todays dollars, and can now be bought for less than $100. They definitely were made well.

My first scope was a Knight Kit scope. I saved all school year and when summer vacation came I spent $109, if it recall, to purchase the kit and spent the summer putting it together.

This scope was only about 2 Mhz tops. But, I learned so much from it being able to "see" how so many electronic circuits worked and then start trying out designing my own circuits and projects, and seeing how they worked, or needed improvement.

This scope was my first realization that professionally designed equipment could be improved and not accepted as correct without question.  

My first experience was when a electrolytic capacitor exploded with a loud bang when I first plugged the scope in, as I waited breathlessly for the thrill of seeing my summers's work come to life in a magic little green line.

I was able to reason out the voltage rating of the capacitor (part of a cathode resistor negative bias circuit) was exceeded momentarily, on start up, so I got on my bicycle, rode down to the local electronics store and was able to confidently buy a replacement was not the exact same value. But, higher voltage and a close, but larger, capacitance value.

My second design improvement came after I discovered the wonders of the Z axes. I was having a great time feeding the video from a TV set I was fixing for a neighbor into the Z axis, syncing up the horizontal and feeding in the vertical to the X axis, and watching TV on my oscilloscope screen.  

There was a little RCA plug that shorted the Z axis input on the back of the scope when it was not in use. 

I'd been using the scope and realized I'd not replaced the shorting plug. The Z axis input was essentially a .1uF capacitor connected to the cathode of the CRT at 1,200 volts. 

I reached over and behind the scope to plug in the shorting plug. I remember how the little plug made such a loud bang as it hit the wall on the opposite side of my room. And how stunning the jolt was traveling through me. 

My next design improvement was to solder a 1M ohm resistor across the Z axis connector, inside the scope, to let the capacitor charge and equalize to the 1,200 volts on its own. So I would not become a live demonstration of RC time constants and capacitor peak charging current again.

Tom, wb6b



Re: Replacing firmware Ubitx V5 problems

Herman Scheper
 

Gary,

 

 

Tnx for this reaction. Now back home and i will give it this afternoon a try.

 

I did NO Ubitx modifications. I build it in a case bought from : https://amateurradiokits.in/ ( case for 5” screen )

 

First build it in this case, aligned it and it worked as promised.

 

After that I starting replacing the firmware.   I never used Arduino etc, so i hav a lack of knowledge.

 

But I will fix it sometimes.

 

 

I have a Prusa 3D printer and learned how to upgrade the firmware; so this will go also one of this days.

 

Many tnx for your helpfull answers.

 

Regards,  Herman

 

 

Van: BITX20@groups.io <BITX20@groups.io> Namens Gary Anderson
Verzonden: woensdag 31 juli 2019 05:03
Aan: BITX20@groups.io
Onderwerp: Re: [BITX20] Replacing firmware Ubitx V5 problems

 

Herman,
"30630 bytes uploaded" OK!
30630 looks correct for "UBITXV5_CEC_V1.122_NX_S.hex"  
:0A779C00732C207365742000220096  last ten (OA) bytes are loaded at address 0x779C
this is an intelHEX file, Not a binary file.  File size will not match bytes uploaded.

It is unclear where you are in uBITX modifications.  I did see that you own an enhanced Nextion.
I suggest starting with the factory LCD display installed and test that you can successfully upload the CEC firmware that matches the factory supplied display. 
I believe it is UBITXV5_CEC_V1.122_16P (for a single 1604 display via the Parallel interface)

Regards,
Gary

Re: Replacing firmware Ubitx V5 problems

Herman Scheper
 

Gary,

 

 

I ive it a try and it works now agian.

 

Now find out ho to calibrate or is better first now connect Nextion 5 and change software again…??

 

 

herman

 

Van: BITX20@groups.io <BITX20@groups.io> Namens Herman Scheper
Verzonden: donderdag 1 augustus 2019 13:07
Aan: BITX20@groups.io
Onderwerp: Re: [BITX20] Replacing firmware Ubitx V5 problems

 

Gary,

 

 

Tnx for this reaction. Now back home and i will give it this afternoon a try.

 

I did NO Ubitx modifications. I build it in a case bought from : https://amateurradiokits.in/ ( case for 5” screen )

 

First build it in this case, aligned it and it worked as promised.

 

After that I starting replacing the firmware.   I never used Arduino etc, so i hav a lack of knowledge.

 

But I will fix it sometimes.

 

 

I have a Prusa 3D printer and learned how to upgrade the firmware; so this will go also one of this days.

 

Many tnx for your helpfull answers.

 

Regards,  Herman

 

 

Van: BITX20@groups.io <BITX20@groups.io> Namens Gary Anderson
Verzonden: woensdag 31 juli 2019 05:03
Aan: BITX20@groups.io
Onderwerp: Re: [BITX20] Replacing firmware Ubitx V5 problems

 

Herman,
"30630 bytes uploaded" OK!
30630 looks correct for "UBITXV5_CEC_V1.122_NX_S.hex"  
:0A779C00732C207365742000220096  last ten (OA) bytes are loaded at address 0x779C
this is an intelHEX file, Not a binary file.  File size will not match bytes uploaded.

It is unclear where you are in uBITX modifications.  I did see that you own an enhanced Nextion.
I suggest starting with the factory LCD display installed and test that you can successfully upload the CEC firmware that matches the factory supplied display. 
I believe it is UBITXV5_CEC_V1.122_16P (for a single 1604 display via the Parallel interface)

Regards,
Gary

Re: CLKn frequencies for uBITx v5

Ravi Miranda
 

Hi Jerry,

Thank you very much for this.

Hopefully this should sort out my woes.

Best 73,

Ravi/M0RVI

On Thu, 1 Aug 2019 at 03:55, Jerry Gaffke via Groups.Io
<jgaffke=yahoo.com@groups.io> wrote:

Ravi,

Take a look at this old post:
https://groups.io/g/BITX20/message/44515

Jerry, KE7ER


On Wed, Jul 31, 2019 at 04:53 AM, Ravi Miranda wrote:

I'm still trying to understand how the frequencies (3 of them)
interact and produce the final output.



--
I'm here to add more value to the world than I'm using up.

Re: ubitx with Icom SM-6 desk mic

Skip Davis
 

John this mic will work fine all you will need to do is either make an adapter cable or replace the connector with a stereo 3.5mm/ 1/8” plug. 
Wire pin 1 to the tip/mic (with bias voltage) pin 7 to sleeve and either pin 6 or 5 to sleeve also, then pin the other not connected pin 5/6 to ring. You should be good to go and only need to adjust the mic gain pot for drive level. 

Skip Davis, NC9O

On Aug 1, 2019, at 04:46, John Scherer <jrsphoto@...> wrote:

I've got an Icom SM-6 desk mic sitting around and I'd love to wire this up to my ubitx v5.  Its clear that this mic has its own preamp and I'm not certain if I need to make any changes for this mic to work.

http://www.radiomanual.info/schemi/ICOM_ACC/Icom_SM-6_user.pdf

--
John - N0CTL - Fulltime RV in a 40' motorhome

New uBitX - Start up Questions...

Steven
 

Hi All! I'm Steven KM4WIP. I have just completed assembly of a uBitX. It was my reward for passing the Extra Class exam last month.

The rig is built on a metal baking pan. When I plug in the 12v line, it lights up right away, that is good news. The on/off switch seems to only work with volume - is this correct? Volume does work.The VFO push button works, I can get to menu choices. I heard some garbled SSB and some clear CW on 40m. It won't transmit. And there is no CW sig at key down.

So here's my most obvious question. With the mike plugged in the VFO just sits on (I think ) 7.500 MHz. When I unplug the mike I can tune the VFO. Any clues?

Also is there an initial set up I need to run, or should this rig be able to plug in, tune in, and transmit?

Thanks!!!
Steven KM4WIP

Re: Cool cheap oscilloscope for troubleshooting

Lawrence Galea
 

How abut home brewing a digital wattmeter?

And a Capacitance / inductance meter
https://sites.google.com/site/vk3bhr/home/index2-html 

Enjoy 
Lawrence

On Thu, Aug 1, 2019 at 12:03 PM Tom, wb6b <wb6b@...> wrote:
Someone told me they saw an old Tektronix 465 scope on eBay for $50 (probably $150 shipping :) ). That could be a good route. Hard to imaging that those scope might have cost $20,000 or more in todays dollars, and can now be bought for less than $100. They definitely were made well.

My first scope was a Knight Kit scope. I saved all school year and when summer vacation came I spent $109, if it recall, to purchase the kit and spent the summer putting it together.

This scope was only about 2 Mhz tops. But, I learned so much from it being able to "see" how so many electronic circuits worked and then start trying out designing my own circuits and projects, and seeing how they worked, or needed improvement.

This scope was my first realization that professionally designed equipment could be improved and not accepted as correct without question.  

My first experience was when a electrolytic capacitor exploded with a loud bang when I first plugged the scope in, as I waited breathlessly for the thrill of seeing my summers's work come to life in a magic little green line.

I was able to reason out the voltage rating of the capacitor (part of a cathode resistor negative bias circuit) was exceeded momentarily, on start up, so I got on my bicycle, rode down to the local electronics store and was able to confidently buy a replacement was not the exact same value. But, higher voltage and a close, but larger, capacitance value.

My second design improvement came after I discovered the wonders of the Z axes. I was having a great time feeding the video from a TV set I was fixing for a neighbor into the Z axis, syncing up the horizontal and feeding in the vertical to the X axis, and watching TV on my oscilloscope screen.  

There was a little RCA plug that shorted the Z axis input on the back of the scope when it was not in use. 

I'd been using the scope and realized I'd not replaced the shorting plug. The Z axis input was essentially a .1uF capacitor connected to the cathode of the CRT at 1,200 volts. 

I reached over and behind the scope to plug in the shorting plug. I remember how the little plug made such a loud bang as it hit the wall on the opposite side of my room. And how stunning the jolt was traveling through me. 

My next design improvement was to solder a 1M ohm resistor across the Z axis connector, inside the scope, to let the capacitor charge and equalize to the 1,200 volts on its own. So I would not become a live demonstration of RC time constants and capacitor peak charging current again.

Tom, wb6b



Re: Cool cheap oscilloscope for troubleshooting

Jack, W8TEE
 

Here's a picture of a "miniature" version of the Nov, 2018, QST article. It substitutes a 200W RF resistor (hiding between the orange and black wire) for the resistor network/oil bath. It has a small heatsink on the back so it can handle 50W for about 30 seconds and costs less than $20 to build. It fits in your shirt pocket.

Inline image

Jack, W8TEE

On Thursday, August 1, 2019, 9:19:31 AM EDT, Lawrence Galea <9h1avlaw@...> wrote:


How abut home brewing a digital wattmeter?

And a Capacitance / inductance meter
https://sites.google.com/site/vk3bhr/home/index2-html 

Enjoy 
Lawrence

On Thu, Aug 1, 2019 at 12:03 PM Tom, wb6b <wb6b@...> wrote:
Someone told me they saw an old Tektronix 465 scope on eBay for $50 (probably $150 shipping :) ). That could be a good route. Hard to imaging that those scope might have cost $20,000 or more in todays dollars, and can now be bought for less than $100. They definitely were made well.

My first scope was a Knight Kit scope. I saved all school year and when summer vacation came I spent $109, if it recall, to purchase the kit and spent the summer putting it together.

This scope was only about 2 Mhz tops. But, I learned so much from it being able to "see" how so many electronic circuits worked and then start trying out designing my own circuits and projects, and seeing how they worked, or needed improvement.

This scope was my first realization that professionally designed equipment could be improved and not accepted as correct without question.  

My first experience was when a electrolytic capacitor exploded with a loud bang when I first plugged the scope in, as I waited breathlessly for the thrill of seeing my summers's work come to life in a magic little green line.

I was able to reason out the voltage rating of the capacitor (part of a cathode resistor negative bias circuit) was exceeded momentarily, on start up, so I got on my bicycle, rode down to the local electronics store and was able to confidently buy a replacement was not the exact same value. But, higher voltage and a close, but larger, capacitance value.

My second design improvement came after I discovered the wonders of the Z axes. I was having a great time feeding the video from a TV set I was fixing for a neighbor into the Z axis, syncing up the horizontal and feeding in the vertical to the X axis, and watching TV on my oscilloscope screen.  

There was a little RCA plug that shorted the Z axis input on the back of the scope when it was not in use. 

I'd been using the scope and realized I'd not replaced the shorting plug. The Z axis input was essentially a .1uF capacitor connected to the cathode of the CRT at 1,200 volts. 

I reached over and behind the scope to plug in the shorting plug. I remember how the little plug made such a loud bang as it hit the wall on the opposite side of my room. And how stunning the jolt was traveling through me. 

My next design improvement was to solder a 1M ohm resistor across the Z axis connector, inside the scope, to let the capacitor charge and equalize to the 1,200 volts on its own. So I would not become a live demonstration of RC time constants and capacitor peak charging current again.

Tom, wb6b



Re: AMP FOR UBITX

bill steffey NY9H
 

already got rid of one  k3 ./p3,,,,,,


bill

On 7/31/2019 11:09 PM, Skip Davis via Groups.Io wrote:
So your thinning out the crowd of equipment you have? Are you making room for the K4? Nice to see you are active on the reflectors.

Skip Davis, NC9O
On Jul 31, 2019, at 19:11, bill steffey NY9H <Ny9h@...> wrote:

FINALLY GIVING UP MY TT 405 AMP ... ON EBAY


WORKED GREAT WITH MY UBITX !!!

BILL NY9H



Re: AMP FOR UBITX

Ron Stauffer
 

I cannot find it on ebay


From: BITX20@groups.io <BITX20@groups.io> on behalf of bill steffey NY9H <Ny9h@...>
Sent: Thursday, August 1, 2019 8:39:10 AM
To: BITX20@groups.io <BITX20@groups.io>
Subject: Re: [BITX20] AMP FOR UBITX
 
already got rid of one  k3 ./p3,,,,,,


bill




On 7/31/2019 11:09 PM, Skip Davis via Groups.Io wrote:
> So your thinning out the crowd of equipment you have? Are you making room for the K4? Nice to see you are active on the reflectors.
>
> Skip Davis, NC9O
>> On Jul 31, 2019, at 19:11, bill steffey NY9H <Ny9h@...> wrote:
>>
>> FINALLY GIVING UP MY TT 405 AMP ...  ON EBAY
>>
>>
>> WORKED GREAT WITH MY UBITX !!!
>>
>> BILL NY9H
>>
>>
>>
>
>
>
>



Re: AMP FOR UBITX

Skip Davis
 

That’s good soooo..... are you on the list for the K4? I’m thinking about it still, if it sounds as good as the KX3 I’m on board. I primarily use the KX3 and really haven’t used the K3 in months.

Skip Davis, NC9O
847-331-4147

On Aug 1, 2019, at 09:39, bill steffey NY9H <Ny9h@...> wrote:

already got rid of one k3 ./p3,,,,,,


bill




On 7/31/2019 11:09 PM, Skip Davis via Groups.Io wrote:
So your thinning out the crowd of equipment you have? Are you making room for the K4? Nice to see you are active on the reflectors.

Skip Davis, NC9O
On Jul 31, 2019, at 19:11, bill steffey NY9H <Ny9h@...> wrote:

FINALLY GIVING UP MY TT 405 AMP ... ON EBAY


WORKED GREAT WITH MY UBITX !!!

BILL NY9H




Re: AMP FOR UBITX

Michael Wells
 

Re: Issues with ordering the BITX40

dk3ts@...
 

Really want the BITX40 but as I have a band specific use for it. The link still appears broken for purchasing since it's still taking me to a generic PayPal page.

Re: New uBitX - Start up Questions...

_Dave_ K0MBT
 

Congrats on the upgrade.

Definitely odd behavior. Is the radio going into transmit when you plug in the mic/ptt? That is what it sounds like to me. Check the wiring make sure that the resistor is across to the ptt.