Date   
W0EB/W2CTX/N5IB BITeensio construction Warning concerning the Teensy 3.5 or 3.6 #ubitx

Jim Sheldon
 


I just posted the following warning to the www.w0eb.com website and want to make sure everyone that has constructed or is constructing one of our BITeensio boards gets the following critical information.

WARNING!
It has recently come to my attention that the tiny power jumper on the back of the Teensy 3.5 or 3.6 MUST be cut when using external power to the Teensy (from the BITeensio board). Left intact, it is possible to have power being applied to the Teensy through BOTH the BITeensio board AND the USB connection, especially during programming or remote control operation via the USB port. This causes board power and USB power to conflict with each other and can destroy the Teensy. The jumper is pointed out on the back side of the pin-out card that comes with every Teensy and it states: "Cut to separate VIN from VUSB, if using a battery charger or external power." with an arrow pointing to the jumper between the two pads.

Carefully cut this tiny jumper with a very sharp hobby knife to avoid any possible problems.  After cutting the jumper, you will have to power the board externally through the BITeensio card (or other means) when programming or re-programming the Teensy through the USB port.  This holds true for Teensy boards used in just about any application, not just on our BITeensio board.

Jim Sheldon, W0EB
http://www.w0eb.com

Re: ND6T AGC and Click kit wiring notes

Kees T
 

Yes, it indicates the header "pair" ....just like on the Audio header pair .....not enough room. Be sure to instal the jumper if you are not using the RF Gain potentiometer.

Nice job on the board assembly. I see you got the diodes soldered in place.

73 Kees K5BCQ

 

Re: Rx Radio #ubitx-help

Mike aka KC2WVB <rb5363@...>
 

I guess I don't understand because to receive 3 through 30 Mhz aside from an antenna you simply turn the knob on the VFO and with this radio if your in 'say' 7 Mhz and you want to listen to 3 Mhz then press the encoder to enter the menu. Follow the menu's change frequency prompts an you easily get to 3 Mhz otherwise it takes a lot of turning of the knob to lower from 7 to 3.


On Fri, Jun 22, 2018, 7:14 AM sridhar <vu3pen@...> wrote:
thx for valuable suggestions , i am also using the wire  antenna to  receive SW RX  ,  40 feet on AIR , then 40 vertical means total 80 feet is using , the wire is normal AC wire used for the house internal wring , for the same wire if i put 12 band normal radio , the audio is coming .
(I will try with 58 feet also in air later )

But my question i in UBITX set how can i receive SW  frequency 3 to 30 Mhz Stations ? for got the antenna which i am feeding i had many options to feed the antenna 

de 
vu3pen
sridhar

Re: experience with Sunil VU3SUA's enclosures #ubitx

Mike aka KC2WVB <rb5363@...>
 

I agree, my case arrived in 3 and 1/2 weeks as per ordered.  Nice enclosure too and with pots and etc that match the case....


On Fri, Jun 22, 2018, 5:19 AM Kevin Luxford <kbgluxford@...> wrote:
Sunil has a list of countries to which he can send goods via DHL.  If
your country is not on the list, you will have to receive your order via
India Post.  This can take four weeks or more (to Australia).  I have
found Sunil responsive to emails.  I acknowledge that my experiences may
not be similar to yours, but apart from the lack of tracking information
from India Post, and the long time it takes to get stuff via their
service, I have so far found everything has got here in an undamaged state.

vy 73
Kevin VK3DAP / ZL2DAP




Re: Rx Radio #ubitx-help

iz oos
 

You have to press the vfo choose the band eg 14mhz and then using the vfo again. I have the original firmware version 3 installed and once you get acquainted it is somehow fast albeit a bit erratic.


Il 22/giu/2018 17:35, "Mike aka KC2WVB" <rb5363@...> ha scritto:
I guess I don't understand because to receive 3 through 30 Mhz aside from an antenna you simply turn the knob on the VFO and with this radio if your in 'say' 7 Mhz and you want to listen to 3 Mhz then press the encoder to enter the menu. Follow the menu's change frequency prompts an you easily get to 3 Mhz otherwise it takes a lot of turning of the knob to lower from 7 to 3.

On Fri, Jun 22, 2018, 7:14 AM sridhar <vu3pen@...> wrote:
thx for valuable suggestions , i am also using the wire  antenna to  receive SW RX  ,  40 feet on AIR , then 40 vertical means total 80 feet is using , the wire is normal AC wire used for the house internal wring , for the same wire if i put 12 band normal radio , the audio is coming .
(I will try with 58 feet also in air later )

But my question i in UBITX set how can i receive SW  frequency 3 to 30 Mhz Stations ? for got the antenna which i am feeding i had many options to feed the antenna 

de 
vu3pen
sridhar

Re: Oscilloscope on sale

Ralph Mowery
 


I have seen on youtube where some have flashed the software in some of the scopes and other devices to raise them up to higher levels.  There may or may not be some small components in them that limit the bandwidth so you may not be able to get the traces to show a true waveform at the higher frequency.

At the least you would have o get better probes for the scope.

The Hanteck 200 mhz scope I have does not seem to do the XY patterns very well.  I have to drop back to my old Tectronic analog to do that.  Maybe a better quality digital scope will do the XY patterns better than my inexpensive Hanteck

de ku4pt





On Fri, Jun 22, 2018 at 11:26 AM, Michael Hagen <motdog@...> wrote:

I got my Rigol on eBay, new just a few hours.  DS1054 for about $370.  Had to do the 100MHZ operation.

They have newer ones now, better, but more $.


I like it, but for the price I think the Hantek 200 MHZ is a better deal, especially since Jack likes his.

Circuit Specialties has sales once in a while, I got 15% off my Spectrum Analyzer from them.

I had problems with the Hantek USB scopes, did not like them.   I would never buy a PC connected scope again.

I seldom use more than 2 channels?

The Rigol is actually TOO SMALL.  Too many features and screen is small, I can't see all the stuff.


Strange, my Rigol  has 1 flaky probe already, AND the Ground Alligators take BIG Muscle to open!

They sure have a real spring in there!  They surprise me every time I clip.

Mike, WA6ISP


_._,_._,_


Re: Thoughts on a Ham Bus

Mike aka KC2WVB <rb5363@...>
 

Steve, I get your analogy if you only look at the surface which is the camel's appearance. On the other hand the camel is a marvelous animal that if you want to think in terms of designed by, evolution, is uniquely adapted to its environment and will perform heads above anything else. So if evolution is the committee it sure knows how to get things right.


On Wed, Jun 20, 2018, 11:18 PM Steve Black via Groups.Io <kb1chu=aol.com@groups.io> wrote:

A camel is a horse designed by committee. Steve kb1chu


On 06/20/2018 10:50 PM, Jack Purdum via Groups.Io wrote:
Arv:

All tough questions, but worth answering. Think of the possibilities. Personally, I think this should be of the free-to-use license, mainly because I don't want to see extensions to the bus that aren't under someone's control. Otherwise, the standard slowly dissolves into chaos.

Every time an organization question comes up, I think of a sign I had on my desk when I was the department chairman:

    For God so loved the world, he didn't send a committee.

Still, there has to be a small knot of knowledgeable people who know the EE and software side of this. It needs to be small because it needs to be nimble, yet with enough technical depth to make things work. I've seen the agony of trying to define a standard (i.e., the X3J11 committee to write the first standard for the C language)...it is a formidable task, and the difficult increases with the size of the committee. There are all kinds of technical details to think about and the Atlas bus would at least be a thoughtful starting point.

I think this could be a rewarding endeavor.

Jack, W8TEE



On Wednesday, June 20, 2018, 8:36:53 PM EDT, Arv Evans <arvid.evans@...> wrote:


If hams were to design and standardize a ham-bus-system approach to modular equipment,
should the design be placed in public domain, or under one of the free-to-use licenses?  
Should a group be formed specifically for the purpose of bus design, documentation, and
publication?
How would upgrades, modifications, and alternative bus designs be handled?

Seems there are lots of questions, lots of possible opinions, and lots of work to do.

Arv

Re: Oscilloscope on sale

R. Kuehn
 

Just to throw another good scope in the mix is the Siglent 1202X-E for $380. 2 channels, 200MHz all the bells and whistles come unlocked, no hacking necessary. A great scope, I love it.

Eevblog did a review about a year ago, 

Ralph
N9WTX


On Fri, Jun 22, 2018 at 10:52 Ralph Mowery <rmowery42@...> wrote:

I have seen on youtube where some have flashed the software in some of the scopes and other devices to raise them up to higher levels.  There may or may not be some small components in them that limit the bandwidth so you may not be able to get the traces to show a true waveform at the higher frequency.

At the least you would have o get better probes for the scope.

The Hanteck 200 mhz scope I have does not seem to do the XY patterns very well.  I have to drop back to my old Tectronic analog to do that.  Maybe a better quality digital scope will do the XY patterns better than my inexpensive Hanteck

de ku4pt





On Fri, Jun 22, 2018 at 11:26 AM, Michael Hagen <motdog@...> wrote:

I got my Rigol on eBay, new just a few hours.  DS1054 for about $370.  Had to do the 100MHZ operation.

They have newer ones now, better, but more $.


I like it, but for the price I think the Hantek 200 MHZ is a better deal, especially since Jack likes his.

Circuit Specialties has sales once in a while, I got 15% off my Spectrum Analyzer from them.

I had problems with the Hantek USB scopes, did not like them.   I would never buy a PC connected scope again.

I seldom use more than 2 channels?

The Rigol is actually TOO SMALL.  Too many features and screen is small, I can't see all the stuff.


Strange, my Rigol  has 1 flaky probe already, AND the Ground Alligators take BIG Muscle to open!

They sure have a real spring in there!  They surprise me every time I clip.

Mike, WA6ISP


Re: Somethings gone wrong!

M0CLS
 

Now the reception/audio is in and out too! Like a poor connection somewhere but I have searched for the last hour and can see no loose connections anywhere! 

Re: Somethings gone wrong!

Derrick Young <deyoung10@...>
 

Suspect you have a cold solder joint.  Go back and inspect what you did.

Derrick
W4DEY

W8TEE Power/SWR Sketch for Nano

Kees T
 

Jack,

Don't you have an Arduino sketch for a Nano which uses AD8307s for input and outputs to a 16x2 screen or one of the 1" OLED displays via I2C ?

73 Kees K5BCQ   

Re: W8TEE Power/SWR Sketch for Nano

Jack Purdum
 

I do have code for the 0.96" OLED's, as that's what we used for the DL I've mentioned before. Do you need it?

Jack, W8TEE

On Friday, June 22, 2018, 12:52:17 PM EDT, Kees T <windy10605@...> wrote:


Jack,

Don't you have an Arduino sketch for a Nano which uses AD8307s for input and outputs to a 16x2 screen or one of the 1" OLED displays via I2C ?

73 Kees K5BCQ   

Re: Understanding Spurious Emissions

Jerry Gaffke
 

I wouldn't operate the transmitter on 15m,12m,10m without
either a fix for the spur or some way to monitor it.

Monitoring could be done with a second receiver plus a step attenuator.
Transmit into a dummy load while monitoring the spur at 44.995mhz-Fop through a step attenuator, 
where Fop is your operating frequency.
So if you are operating at  Fop = 29.0 mhz, the spur is at 44.995-29=15.995mhz, give or take a couple khz. 
Determine the signal strength of the spur, perhaps using the receiver S-meter.
Then tune in your operating frequency, and use the step attenuator to reduce the strength of your main signal
into the dummy load until you get the same S-meter reading as you did for the spur.
The additional attenuation required tells you how many dB below your main signal that spur is.
A good source for a step attenuator is the "Attenuator Kit #13" from Kees:  http://www.qsl.net/k5bcq/Kits/Kits.html

If you can't be bothered to do the procedure above, it may not be a good idea to be transmitting 
on the 15m, 12m and 10m bands using the uBitx.
This is especially true if you have jacked up your mike gain somehow to get more power out,
or are running your uBitx into a high powered external amplifier.

Some do report that a properly adjusted uBitx can have that spur down near the legal limit
of 43 dB below the main signal.  But that is pretty much the best possible case.
Your best possible case could be much worse, the gain of the 45mhz amp in particular will be
all over the map depending on the characteristics of the mmbt3904's that happen to be in your rig.
And it will definitely get worse if you raise the mike gain, or shout into the mike.
We seem to know the best case, I would want to know my worst case 
before attempting to operate on these upper bands. 


There are several solutions to this.

We could call it a rig suitable for operation from 160m to 17m, forget the upper bands,
replacing the top transmit LPF with one suitable for 160m.

We could replace the 30mhz LPF at L1,2,3,4 with different filters for each band.
This is what pretty much all other HF transceivers do.

Or we could raise the first IF frequency from 45mhz to something well above 60mhz,
perhaps the 86.85mhz of post   https://groups.io/g/BITX20/message/52460
Since 86.85mhz - 30mhz puts the lowest possible frequency for the spur at 56.85mhz,
the spur won't get through the stock 30mhz LPF at L1,2,3,4


I'd prefer to see a fix that replaces the 45mhz IF, everything there including those two diode ring mixers.
This could be a small daughterboard that mounts into the holes remaining when the mixer transformers are removed.
All 6 mmbt3904's would be replaced with BFR106's, the 86.85 mhz PX1002 is used as the filter,
the mixers redesigned for 86mhz.  Gains would be adjusted in both IF amps to minimize the spurs,
and also minimize the carrier we have leaking through.
Parts count and topology remain the same as the stock uBitx, no added complexity,
though we could add some sort of RF AGC attenuator for some extra pennies.
The better transistors will allow an even drive to the PA, giving us a better shot at getting
the same power out to the antenna on 10m as on 80m.
Total cost of parts can be under $10, so it might be a kit that sells for $20 at sufficient volume.
If hfsignals decides to move in this direction, the only significant hit on cost or procurement
would be the $6 PX1002 (volume pricing) vs the custom built 45mhz crystal filter (whatever that costs).
This has not yet been tried.

Jerry, KE7ER


On Fri, Jun 22, 2018 at 05:18 am, ajparent1/KB1GMX wrote:
No, your analogy would be right if you were on the wrong side of the road. 
If you get near even fully driving the modulator the last mixer is easily 10+ db
past saturated as result of there being enough IF gain to assure that.

For those that never go above 20Mhz its adequately filtered and not an issue.

Allison
#############
Howard Fidel  June 21   #52728

Got it. Thanks. I never saw on my uBitx the numbers you reported, but I don't think it is a serious problem for a barefoot uBitx, which is the main point I was trying to make. It seemed like the group was spending a lot of energy on something that is like driving 60 MPH in a 55 zone. 

Re: W8TEE Power/SWR Sketch for Nano

Jack Purdum
 

Kees:

It appears that a good part of the code was taken from the Adafruit library examples:




On Friday, June 22, 2018, 12:54:39 PM EDT, Jack Purdum via Groups.Io <jjpurdum@...> wrote:


I do have code for the 0.96" OLED's, as that's what we used for the DL I've mentioned before. Do you need it?

Jack, W8TEE

On Friday, June 22, 2018, 12:52:17 PM EDT, Kees T <windy10605@...> wrote:


Jack,

Don't you have an Arduino sketch for a Nano which uses AD8307s for input and outputs to a 16x2 screen or one of the 1" OLED displays via I2C ?

73 Kees K5BCQ   

Re: Oscilloscope on sale

Jerry Gaffke
 

I think that upgrade trick was mostly for the $400 Rigol DS1052E 50mhz scope.
Rigol was selling a 100mhz scope for extra bucks that was identical except for the firmware,
strictly a marketing decision.

Now that there are scopes under $300 with a bandwidth of 200mhz (assuming they work),
the gloves are off, I'd guess they're all going for max bandwidth for minimum cost.
And if somebody is crippling their hardware, they likely make it harder to upgrade
on the cheap having seen what happened with the Rigol. 

Jerry, KE7ER



On Fri, Jun 22, 2018 at 08:52 am, Ralph Mowery wrote:
I have seen on youtube where some have flashed the software in some of the scopes and other devices to raise them up to higher levels.  There may or may not be some small components in them that limit the bandwidth so you may not be able to get the traces to show a true waveform at the higher frequency.
 
 

Re: W8TEE Power/SWR Sketch for Nano

Kees T
 

That's the one. We're putting together a 25mW to 25W Power SWR meter (.....like who isn't) and have a great bidirectional coupler, the AD8307s, some Op-Amps as needed for level control and calibration, a Nano, and several of those displays. Makes a nice combination for a uBITX. The only thing I lack is the firmware. We have use those OLEDs in a couple of devices and (if they don't generate too much interference) look very nice and super sharp....FWD, REV, VSWR, ? Could also drive it with one of the many signal generators out there to allow a low level antenna "Tune" function for the attached Transceiver. 

We also have a LED bargraph version which requires NO firmware ....but it's only $2-3 less and lacks being as user friendly. You guys who write the firmware control the road.

73 Kees K5BCQ

Re: RF Situation Resolved.

hotrod541@...
 

I just need some clairifaction on replacing the heat sinks on uBITX.  I am in the process of maching out a new heat sink, which will be one piece.  If I am correct,  if I mount each FET with the correct mounting pads and they don't touch they should work fine or am I missing something here.  I just don't want to manufacture a problem. 
Thanks, 73
Buddy, KJ4ZSI

Re: RF Situation Resolved.

M Garza <mgarza896@...>
 

One big heatsink is fine, as long as both FETs are insulated from it.

I plan on doing this, once I get to putting things in a case.

Marco - KG5PRT 


On Fri, Jun 22, 2018, 12:14 PM <hotrod541@...> wrote:
I just need some clairifaction on replacing the heat sinks on uBITX.  I am in the process of maching out a new heat sink, which will be one piece.  If I am correct,  if I mount each FET with the correct mounting pads and they don't touch they should work fine or am I missing something here.  I just don't want to manufacture a problem. 
Thanks, 73
Buddy, KJ4ZSI

Re: Homebrew from scratch #ubitx

Peter Carr
 

I have just built a uBITX with standard components (no SMD's) from scratch on a PCB I designed - it works well.  I have now designed another PCB which incorporates the Arduino NANO and the the Si5351 shield and I'm just waiting for the PCB's to arrive and then I will start assembling.  I made some changes to the circuit to allow for a dynamic microphone and the use of screened TOKO cols for the 30MHz lowpass filter, I also changed the coupling arrangement to the 45MHz filter.

I have attached a picture of the original PCB and a PDF of the new layout incorporating the Arduino and Si5351

Maybe one day I will play with SMT but for now standard components are still easily available !
 
73's - Peter M0HYT

Re: RF Situation Resolved.

Latham, Chip
 

Make sure you are using an insulating kit including the screws and the back either mica or other insulator. No continuity between the gates after mounting the irf510's
Using the insulating mounts you wont have to worry about the 12DC being shorted to ground by accident if using a metal case. Since the IRF510 are 180 degrees out of phase if they short on the heat sink you will blow them, like I did.
Hope that helps