Date   
Re: Made Mods to V3 uBitx - no longer transmitting #ubitx-help #v3

_Dave_ AD0B
 

According to the diagram in #76128, it appears that 1/16 control the  coil.
--
73
Dave
k0mbt
Raduino bracket and Ham_Made_Keys

Re: Made Mods to V3 uBitx - no longer transmitting #ubitx-help #v3

 

Correct!

At 18-02-20, you wrote:
Let me see if I understand, as I stated above, the pin numbers on the relays as viewed from BELOW are as follows:
8 9
5 12
3 14

1 16

Instead, the pins numbers are:
1 16
3 14
5 12
(<<<<<note the gap between the pins on the physical relays)
8 9

Correct? Do pins 8 and 9 control the switching mechanism?

Re: Portable antenna(s) #antennas #v6

N1EDC
 

With regards tonsoace considerations, if you are going with a 20m monoband the support system could be pretty simple.

My first portable antenna mast was a 20ft Shakespeare Wonderpole that can be had for not much over $20 and is very light.  You could support a sloper EFHW for 20m with that.  I often leave the top section collapsed (for greater rigidity) and set up a 40m EFHW in an inverted V with that very setup.

I also have a Jackite 33ft pole that could do a 20m EFHW as a straight vertical, but that is significantly more in cost, weight, and guying requirements.

Re: Made Mods to V3 uBitx - no longer transmitting #ubitx-help #v3

Steve - KE0VCD
 

Let me see if I understand, as I stated above, the pin numbers on the relays as viewed from BELOW are as follows:
8    9
5   12
3   14

1   16

Instead, the pins numbers are:
1    16
3   14
5   12
            (<<<<<note the gap between the pins on the physical relays)
8    9

Correct?   Do pins 8 and 9 control the switching mechanism? 

TSW Teensy 4.0 software with RTC coming soon #ubitx #v6

Jim Sheldon
 

To all users of TSW's Teensy4 to NANO adapter and those thinking about getting one, we have successfully gotten the T4's internal real time clock to display the time on the upper left of the screen. We still have a few refinements that we're working on so it isn't ready for prime time just yet.  Right now, you simply touch on the clock display and that brings up a manual setting window.  We hope to have an alternate, more accurate means of setting the clock in the future, such as an attached GPS module or grabbing your computer's time via the USB port.  Maybe even both, with the GPS being an option.  Possibilities here appear to be close to endless.

One of the drawbacks, we are still trying to find a 3V coin cell holder that can be mounted either on the Adapter or the Teensy 4 itself, connected to the Vbat (back up battery) terminal on the Teensy to keep the clock accurate while main power is off. Right now we're having to make up one that's connected by a set of wires and just hung off of it. Mounting it on the adapter or Teensy interferes with the regulator's heat sink on the factory Raduino AND the speaker on the top cover of the factory case.  Not an elegant solution but it is usable for the time being.

We've also added an A>B button that will transfer the frequency in VFO A to VFO B as the basis for easier setup of the SPLIT function. Screen shot shows how the screen looks in our "Beta" test (may change slightly in the coming release version)

We hope to be able to release a usable version within the next few days so watch for it on the website.

Jim Sheldon, W0EB,
TSW Project Coordinator

Re: Save power supply voltage for uBitx V6

Curt
 

Eugen

a commercial 13.8 volt supply should be fine - I was waiting for someone else to answer since I have a v4 -- but v6 should be same in this regard. 

the caution is to folk who try to make a power supply with a wall-wart - and get 18 volts instead of 12 or 14 volts into their receiver (and nearly 0 volts into their transmitter if the receiver survives!). 

enjoy your new rig - and I agree with your caution.  some folk insist on having a fuse in the path if they connect their uBITX to a 20-40 amp power source. 

73 curt
aka Curtis Eugene Milton wb8yyy

Re: Replace Si5351 and Raduino with Teensy4?

Jim Sheldon
 

Not only would frequency precision be an issue, but stability also.  They use micro miniature crystals on the Teensy 4.0 and also you would have to be able to generate 3 simultaneous and different clock frequencies.  The Si5351 does this well enough even with all it's warts. 

Jim - W0EB

------ Original Message ------
Sent: 2/18/2020 3:33:48 AM
Subject: [BITX20] Replace Si5351 and Raduino with Teensy4?

First, let me apologise if this is a stupid question - IANAEE and IANARFE (I am not an electrical engineer and I am not an RF engineer).

The new Teensy4 is a monster, running at 600 MHz. If I understand correctly, the Si5351 in the uBitx needs to produce a maximum of 75 MHz, which is done as a square wave.

Could you replace the Raduino and Si5351, with just a Teensy4, using the Teensy to generate the clock signal?
If so, would there be any value in doing it?

I'm guessing frequency precision might be an issue.

Thanks for a great forum.
Ben

Re: Save power supply voltage for uBitx V6

Dean Souleles
 

Hi Eugen,

It should work fine with either. I run mine off a 13.8V benchtop supply - along with the rest of my gear.  I have also used a 12V L-ion battery in the field.

73,

Dean
KK4DAS

Re: Made Mods to V3 uBitx - no longer transmitting #ubitx-help #v3

 

Dave,

Yes, I tried with smaller inductors and did not work at all. It has to be TDK shielded ones.
Changing KT1/2/3 to RF relays like Axicom does the same thing, prevents L5/7 from picking
up the TX signal and recycling it.

If everything worked the first time I would have lost interest in EE 50 years ago!

Raj


I once replaced the L5 and L7 inductors and my radio went to sleep. No matter how well you modify the circuit Raj, there is always someone (me) who doesn;t get it right. I think the values that I used were too small and attenuated the signal. I went ahead and replaced them with stock components and got it working again.

I have no doubt that you or I would have it purring along, Steve isn't there yet but may be gaining.
--
73
Dave
k0mbt
Raduino bracket and Ham_Made_Keys

Re: Portable antenna(s) #antennas #v6

Gordon Gibby
 

Aha!   As Allison i think has shown, RANDOM length end feds, with 9:1's perform terribly from a loss standpoint.
To each, their own.

Gordon



On Tue, Feb 18, 2020 at 6:14 AM Patrick Pelletier <ve9pax@...> wrote:
Hi,

I believe that antenna is an end fed random length wire antenna.  If it were an end fed half wave, the transformer would be a 49:1...

73

Patrick
VE9PAX

On Mon, Feb 17, 2020 at 10:36 PM Ken Hansen <ken@...> wrote:
+1 for EFHW if thTs an option.

I'm not a fan of that particular MFJ portable antenna - it's a series of compromises intended for a specific application, mounted on the back of a QRP Radio.

I'd suggest the 17 ft MFJ telescoping antenna, as well as The full-sized MFJ hamsticks, either one as vertical with a collection of ground radials cut to be resonant on the given band, or as a pair in a 'hamstick dipole' configuration.

Each of the above have 3/8" x 24 stud mounts.

If end-fed is an option, consider building the Hawaii EFHW described here:


They offer a kit, but construction is simple.

Ken, N2VIP

On Feb 17, 2020, at 12:27, KB9WOO <kb9woo@...> wrote:

New to the uBITX, kits, HF, and the group.

Looking for something small, easy, and quick just to get on the air so I'm looking at grabbing a MFJ-1820T single band antenna for 20m, which was designed for the FT-817.  This antenna needs a counterpoise and the 817 apparently has a ground screw on the chassis that the counterpoise is connected to.  I thought I'd just use a clip to attach it to the BNC elbow, or I might even use a small tripod instead.

Mostly just wondering if anyone has used one of these MFJ-18xx antennas with the BITX.  There is also the multi-band 1899t.

--
Mark, kb9woo
Milwaukee, WI uBITX v6

Re: Portable antenna(s) #antennas #v6

Patrick Pelletier
 

Hi,

I believe that antenna is an end fed random length wire antenna.  If it were an end fed half wave, the transformer would be a 49:1...

73

Patrick
VE9PAX


On Mon, Feb 17, 2020 at 10:36 PM Ken Hansen <ken@...> wrote:
+1 for EFHW if thTs an option.

I'm not a fan of that particular MFJ portable antenna - it's a series of compromises intended for a specific application, mounted on the back of a QRP Radio.

I'd suggest the 17 ft MFJ telescoping antenna, as well as The full-sized MFJ hamsticks, either one as vertical with a collection of ground radials cut to be resonant on the given band, or as a pair in a 'hamstick dipole' configuration.

Each of the above have 3/8" x 24 stud mounts.

If end-fed is an option, consider building the Hawaii EFHW described here:


They offer a kit, but construction is simple.

Ken, N2VIP

On Feb 17, 2020, at 12:27, KB9WOO <kb9woo@...> wrote:

New to the uBITX, kits, HF, and the group.

Looking for something small, easy, and quick just to get on the air so I'm looking at grabbing a MFJ-1820T single band antenna for 20m, which was designed for the FT-817.  This antenna needs a counterpoise and the 817 apparently has a ground screw on the chassis that the counterpoise is connected to.  I thought I'd just use a clip to attach it to the BNC elbow, or I might even use a small tripod instead.

Mostly just wondering if anyone has used one of these MFJ-18xx antennas with the BITX.  There is also the multi-band 1899t.

--
Mark, kb9woo
Milwaukee, WI uBITX v6

Save power supply voltage for uBitx V6

Eugen Sibler
 

Dear all
What is the save power supply voltage for the uBitx V6: 12 Volt or 13.6 Volt?
Thanks for your help
Eugen / HB9MDU

Re: Portable antenna(s) #antennas #v6 (portable antennas) #v6 #antennas

David Wilcox <Djwilcox01@...>
 

If you want to read some very interesting information and research about portable antennas let me steer you to Myron, WV0H’s web site:


Look around.  This guy has done a lot of understandable study with test results and lots of photos.  He has a lot of stuff about the end feds and auto transformers among other things antenna related.

Enjoy,

Dave K8WPE 

David J. Wilcox K8WPE’s iPad

On Feb 17, 2020, at 10:57 PM, Gordon Gibby <docvacuumtubes@...> wrote:


I'd like to see some LOSS DATA on that Hawaii endfed.   It is an autotransformer design, but the concern that I have is that the toroid chosen is iron (type #2) permeability = 10.   Using some online calculators, at 40 meters the primary would have about 1.2 microhenries and 50 ohms of inductive reactance.   I think you'd rather see the self-inductance many times that of the resistive impedance desired.....   Would want to see two built back to back, and losses measured.    That test has been humbling to me at times.....

my 2 cents worth.   If anyone has loss data, would be useful for me to hear....
gordon


On Mon, Feb 17, 2020 at 9:36 PM Ken Hansen <ken@...> wrote:
+1 for EFHW if thTs an option.

I'm not a fan of that particular MFJ portable antenna - it's a series of compromises intended for a specific application, mounted on the back of a QRP Radio.

I'd suggest the 17 ft MFJ telescoping antenna, as well as The full-sized MFJ hamsticks, either one as vertical with a collection of ground radials cut to be resonant on the given band, or as a pair in a 'hamstick dipole' configuration.

Each of the above have 3/8" x 24 stud mounts.

If end-fed is an option, consider building the Hawaii EFHW described here:


They offer a kit, but construction is simple.

Ken, N2VIP

On Feb 17, 2020, at 12:27, KB9WOO <kb9woo@...> wrote:

New to the uBITX, kits, HF, and the group.

Looking for something small, easy, and quick just to get on the air so I'm looking at grabbing a MFJ-1820T single band antenna for 20m, which was designed for the FT-817.  This antenna needs a counterpoise and the 817 apparently has a ground screw on the chassis that the counterpoise is connected to.  I thought I'd just use a clip to attach it to the BNC elbow, or I might even use a small tripod instead.

Mostly just wondering if anyone has used one of these MFJ-18xx antennas with the BITX.  There is also the multi-band 1899t.

--
Mark, kb9woo
Milwaukee, WI uBITX v6

Replace Si5351 and Raduino with Teensy4?

knightsbdh@...
 

First, let me apologise if this is a stupid question - IANAEE and IANARFE (I am not an electrical engineer and I am not an RF engineer).

The new Teensy4 is a monster, running at 600 MHz. If I understand correctly, the Si5351 in the uBitx needs to produce a maximum of 75 MHz, which is done as a square wave.

Could you replace the Raduino and Si5351, with just a Teensy4, using the Teensy to generate the clock signal?
If so, would there be any value in doing it?

I'm guessing frequency precision might be an issue.

Thanks for a great forum.
Ben

Nextion not talking to Raduino (but listening to it OK)

kh6sky
 

I have a Ver3 uBitX that at one time functioned OK.  I have moved the unit to a new larger cabinet in recent days and now the 3.5" Nextion no longer responds to touch.  The Nextion responds to the updates from the Raduino. You can change the frequency by turning the encoder tuning knob and it displays correctly on the Nextion. Looking at the two data wires feeding the Nextion with an oscilloscope, I see data on the yellow wire but only a steady high state on the blue wire (when pressing on the display). The only thing I know to have been changed is the Raduino which I re-programmed after mistakenly thinking it had failed.  So my question to the group is if there is any setting in the CEC arduino code that could make the Nextion quit communicating with the Raduino?  Of course, I have the Nextion display selected in the CEC code. 

Tnx
Jim KH6SKY

Re: Made Mods to V3 uBitx - no longer transmitting #ubitx-help #v3

_Dave_ AD0B
 

Yes Raj. had noticed that nothing matched. My experience has mainly involved replacing k1 a couple of times because that it stuck on. Also changing the relays on 3-4 of the ubitx.

I mentioned the reversed relay on k3 and all of the kt thinking that Steve maybe had measured the coil drop on k3. I had also mentioned that the driver transistors being in a low state meaning that they were turned on and in saturation. 

I took one of my v3 ubitx radios apart measuring the signal pathways and indirectly relabeling which side of the relay when where. 

I once replaced the L5 and L7 inductors and my radio went to sleep. No matter how well you modify the circuit Raj, there is always someone (me) who doesn;t get it right. I think the values that I used were too small and attenuated the signal. I went ahead and replaced them with stock components and got it working again. 

I have no doubt that you or I would have it purring along, Steve isn't there yet but may be gaining. 
--
73
Dave
k0mbt
Raduino bracket and Ham_Made_Keys

Re: Portable antenna(s) #antennas #v6

Gordon Gibby
 

Hi Miken.....

Well, you see, those ends are separated in SPACE....and therefore in TIME.    Therefore the superposition of the signals from each end, at any other point, will have to take into account the different DISTANCE (and therefore TIME) from each end, and therefore the PHASES will be affected.

The simple answer is that there will be points where they add, and points where they subtract.   Exactly the same thing like when looking at the effect of the reflected wave off the presumed ground causes antennas to have lobes of maxima and minima in the elevation plane.     I think on one of the exam questions, one has to deal with the impact of various antennas being fed in- or out- of phase and separated by different distances.   AM radio stations do this to create a beam pattern to emphasize their signal in desired directions.   

I've been very effective with a 40-meter half wave antenna operated on its 2nd harmonic from a bus-stop, by the way!   Made some well documented great connections!    So yes, you do radiate quite effective power.

73,

gordon gibby kx4z


On Mon, Feb 17, 2020 at 11:23 PM zl1bnb <mdnewman.nz@...> wrote:
I have my doubts about the effectiveness of end-fed antennas when operated at even harmonics of the half-wave frequency.

Consider an end-fed 80 metre half-wave operated at 40 metres.  One end of the antenna will be radiating a field which is in anti-phase to the field generated by the other end, and surely this will cause cancellation of the emfs developed in in any incident antenna. 

Sure, the antenna can readily be matched, and it may be an efficient radiator, but the opposing fields will generate opposing potentials , causing cancellation.

Where am I wrong?

73 de miken,  zl1bnb

Re: Portable antenna(s) #antennas #v6

zl1bnb
 

I have my doubts about the effectiveness of end-fed antennas when operated at even harmonics of the half-wave frequency.

Consider an end-fed 80 metre half-wave operated at 40 metres.  One end of the antenna will be radiating a field which is in anti-phase to the field generated by the other end, and surely this will cause cancellation of the emfs developed in in any incident antenna. 

Sure, the antenna can readily be matched, and it may be an efficient radiator, but the opposing fields will generate opposing potentials , causing cancellation.

Where am I wrong?

73 de miken,  zl1bnb

Re: Portable antenna(s) #antennas #v6

Gordon Gibby
 

I'd like to see some LOSS DATA on that Hawaii endfed.   It is an autotransformer design, but the concern that I have is that the toroid chosen is iron (type #2) permeability = 10.   Using some online calculators, at 40 meters the primary would have about 1.2 microhenries and 50 ohms of inductive reactance.   I think you'd rather see the self-inductance many times that of the resistive impedance desired.....   Would want to see two built back to back, and losses measured.    That test has been humbling to me at times.....

my 2 cents worth.   If anyone has loss data, would be useful for me to hear....
gordon


On Mon, Feb 17, 2020 at 9:36 PM Ken Hansen <ken@...> wrote:
+1 for EFHW if thTs an option.

I'm not a fan of that particular MFJ portable antenna - it's a series of compromises intended for a specific application, mounted on the back of a QRP Radio.

I'd suggest the 17 ft MFJ telescoping antenna, as well as The full-sized MFJ hamsticks, either one as vertical with a collection of ground radials cut to be resonant on the given band, or as a pair in a 'hamstick dipole' configuration.

Each of the above have 3/8" x 24 stud mounts.

If end-fed is an option, consider building the Hawaii EFHW described here:


They offer a kit, but construction is simple.

Ken, N2VIP

On Feb 17, 2020, at 12:27, KB9WOO <kb9woo@...> wrote:

New to the uBITX, kits, HF, and the group.

Looking for something small, easy, and quick just to get on the air so I'm looking at grabbing a MFJ-1820T single band antenna for 20m, which was designed for the FT-817.  This antenna needs a counterpoise and the 817 apparently has a ground screw on the chassis that the counterpoise is connected to.  I thought I'd just use a clip to attach it to the BNC elbow, or I might even use a small tripod instead.

Mostly just wondering if anyone has used one of these MFJ-18xx antennas with the BITX.  There is also the multi-band 1899t.

--
Mark, kb9woo
Milwaukee, WI uBITX v6

Re: Made Mods to V3 uBitx - no longer transmitting #ubitx-help #v3

 

Dave, in v3 all relays are reversed in pin numbers.

Raj


At 18-02-20, you wrote:
Did you take into account that k1 is mounted inverted when compared to k3 and the kt relays.

[]

It is interesting that the numbering convention used by Ashhar is different than what the relay manufacturers seem to use. 
--
73
Dave
k0mbt
Raduino bracket and Ham_Made_Keys