Date   
Re: grounding #ubitx #ubitx-help

Jerry Gaffke
 

If you are having a problem, you will have to tell us what it is.
Tell us as much as you can about the symptoms.

In answer to your question:
    does the metal enclosure need to be grounded to earth ground?

No.
Doesn't really have to be grounded to anything

If you have your BNC connector mounted to it, then there is a connection 
between your uBitx ground and the metal enclosure.

Generally, we also ground the negative lead of the power supply to the enclosure,
and the ground return on connectors such as mike and key and phones to the enclosure.
The more such grounds to the enclosure, the less likely you are to have extra signals
from wall warts and microwave ovens creeping into your receiver, and low level 
spurs emanating from your transmtter.
But such connections to the enclosure not absolutely necessary.

Jerry, KE7ER


On Wed, Apr 17, 2019 at 12:56 PM, Dennis wrote:
Radunio powers on when plugged into a usb source
   ubitx powers on when not mounted in metal case
   raduino and ubitx power on together when not in metal case

never had to ground any of my other random duino/pi toys

  does the metal enclosure need to be grounded to earth ground?

I am either digging the wrong hole or asking the wrong questions, because I just can't seem to find it.

thanks,
Dennis KL4LG

Re: N6DT AGC and S-meter

rickaputi@...
 

solved!!  thanks to all.  it turns out that the NX_S firmware file is not the correct one as i had assumed.  with some tweaking on the memory manager, it is working great with the N6DT KIt-projects agc board......the s-meter pad on that board connects directly to A7.  Rick WA2TDL.

Re: grounding #ubitx #ubitx-help

Dennis KL4LG
 

the transceiver with only the power connected, and the raduino, will not turn on, while in the metal enclosure i have for the ubitx, I am using a 12 volt lead acid battery as the power source, last I checked it is a lil tired at 12.4ish

burst of harmonics during CW key-down?

Adrian Chadd
 

hi!

I've noticed on my ubitx4 that when you key down for the first CW tone (when it transitions RX->TX and transmits a tone) I get some pretty hefty harmonics out before it settles down. Subsequent CW tones whilst TX is asserted is fine.

It shows up on an LED SWR meter as a quick, bright flicker before it settles in OK.

I'm running the stock firmware with a couple of other bugfixes (like changing LSB<->USB doesn't immediately reprogram in the correct VFO until you change frequency..)

Has anyone else seen this? Is this fixed in Ian's firmware? (I checked out the source code and I can't see anything obviously fixing TX<->RX timing or the order which oscillators are gated/programmed.) Or should I go and dig into it a bit myself?

Thanks!


-adrian

Re: grounding #ubitx #ubitx-help

Evan Hand
 

When ever you plug in the USB port on the Raduino Nano it will power the rest of the Raduino including the display.  The main board is not powered by that usb port, so no sound.  You need to supply the main board with 12vdc to poser the analog portions of the uBitx.

So, lets start at the beginning and verify that 
1 - you have completed the wire up per the HF Signals wiring instructions
2 - That you have installed the resistor for the CW key so that the rig will not go into transmit until you want it to
3 - That you have the proper antenna or dummy load to insure you do not blow the finals

I would suggest stating by powering only the main baord, and not the Power Amp (PA) to start.  Be sure to fuse the input power and connect the reverse polarity diode protection. Having the diode protection has saved my first uBitx.

If you are still having issues, post the symptoms on this thread.  There are a number of people here that will be willing to offer advise.  The one thing to mention when first asking for help is to include what test equipment you might have, e.g. DVM, Oscilloscope, signal generator etc.  That helps in reducing the turn around time for one of the community asking you what test equipment you might have to do the diagnostic.

73 and welcome to the world of uBitx.  The fun is in the learning and solving.
Evan
AC9TU

Re: grounding #ubitx #ubitx-help

Dennis KL4LG
 

1 - rechecked
2 - done originally and rechecked
3 - have a 50 ohm , capable of handling 300watts

I have a fluke 87, I also have access to a couple of older analog o'scopes, and a newer pocket digital that is really just a toy

After I went through and reseated everything (power on the ubitx antenna, digital connector and analog)  again, inside the enclosure, it turns on.
Shaking my head wondering what I did not do the first couple times I checked.

thanks everyone, I am in this for the building and the challenge of learning something new

guess it's time to build the ptt and check the finals after I let the ubitx warm up

Re: grounding #ubitx #ubitx-help

Jerry Gaffke
 

Sounds like it was a bad connection somewhere in the wiring, or perhaps just a flaky power switch.
If it happens again, I suggest you put the multimeter in a mode to measure volts DC,
then put one lead on the battery negative post, with the other lead from the multimeter
measure the voltage at connector P1 pin 1, where 12v enters the board.  It should be 12v.
Also measure P1 pin 2, it should be zero volts.  If both of those are true, you should 
at least hear a bit of static in the headphones when the volume is turned up.

If that works but the Raduino display is not doing anything, I would then measure voltages
at the two outside pins of the big 7805 three pin regulator that hangs off the side of the Raduino.
One of those should be 12v (going in from the main uBitx board), the other should be 5v
(going out to power the Raduino.

Since nothing got hot enough to smoke, I assume it was an open connection, not a short somewhere.
If it had been a short, you would now be wishing you had included Evan's fuse when connecting
battery to the uBitx.

Be very careful when probing not to short anything to an adjacent pin.
In some cases that can destroy something.

Jerry, KE7ER


On Wed, Apr 17, 2019 at 03:04 PM, Dennis wrote:
1 - rechecked
2 - done originally and rechecked
3 - have a 50 ohm , capable of handling 300watts

I have a fluke 87, I also have access to a couple of older analog o'scopes, and a newer pocket digital that is really just a toy

After I went through and reseated everything (power on the ubitx antenna, digital connector and analog)  again, inside the enclosure, it turns on.
Shaking my head wondering what I did not do the first couple times I checked.

thanks everyone, I am in this for the building and the challenge of learning something new

guess it's time to build the ptt and check the finals after I let the ubitx warm up

next ubitx

Michael Mitchell <mitchellmichaelh@...>
 

I would like a 100 W ubitx (maybe maxbitx) the would be ordered and assembled in stages. 
Kit 1...full coverage HOT receiver with good filtration....maybe even sdr based.(especially if one could use a tablet for control and display.
kit 2...!00 W PA
kit 3.. AM, SSB, FM and cw module.
kit 4..!0 meter kit...or any ham band....the rest of the kits will would cover the rest of the ham bands. I see the modules completely sheilded in small metal boxes. They could be stacked in the case.
Price aprox $350 for all the kits.
Dont have to be preassembled if you used through hole. Coils and torroids should be prewound.In other words PCB and parts furnished.

Confusing Directions

Martin KM6TCD
 

 
I'm trying to wire up the BITx40 and quickly reached the point where I was catching mistakes.
 
Called in a more experienced friend who said, "This doesn't make any sense!"
 
Colors of the wires don't match the description.
Photos of the boards don't match be board in front of us.
 
Has anyone run into this problem?
How did you solve it?
 
tks
KM6TCF

Re: burst of harmonics during CW key-down?

Joe Puma
 

Yes search for carrier burst in the threads and you’ll find your answer. I just did the mod on mine. I also noticed that if you have RF issues in the rig it will show a power surge in meter and you might hear some RF noise in speaker during the delay time of a CW unkey. I was getting RF in the pan adapter wire I installed. 

Joe
KD2NFC 



On Apr 17, 2019, at 5:27 PM, Adrian Chadd <adrian@...> wrote:

hi!

I've noticed on my ubitx4 that when you key down for the first CW tone (when it transitions RX->TX and transmits a tone) I get some pretty hefty harmonics out before it settles down. Subsequent CW tones whilst TX is asserted is fine.

It shows up on an LED SWR meter as a quick, bright flicker before it settles in OK.

I'm running the stock firmware with a couple of other bugfixes (like changing LSB<->USB doesn't immediately reprogram in the correct VFO until you change frequency..)

Has anyone else seen this? Is this fixed in Ian's firmware? (I checked out the source code and I can't see anything obviously fixing TX<->RX timing or the order which oscillators are gated/programmed.) Or should I go and dig into it a bit myself?

Thanks!


-adrian

Re: Confusing Directions

Jerry Gaffke
 

Be specific.
Which board do you have?
What directions are you looking at?

There's the Bitx40 and the uBitx, totally different beasts.

And once that's sorted out, give an example of what's wrong.

Re: next ubitx

Ted
 

By all means, let us know when You have the design worked out and circuit board ready for press.  It could be a neat idea.


Ted
K3RTA




Re: burst of harmonics during CW key-down?

Adrian Chadd
 

hi!

Ok, I see the fix for the bitx40 firmware fork. I'll go test it out on afarhan's bitx40 firmware and if it works i'll send him a pull request. Hopefully I can get it into the normal v4 and v5 firmware trees.

Thanks!


-adrian


On Wed, 17 Apr 2019 at 16:39, Joe Puma <kd2nfc@...> wrote:
Yes search for carrier burst in the threads and you’ll find your answer. I just did the mod on mine. I also noticed that if you have RF issues in the rig it will show a power surge in meter and you might hear some RF noise in speaker during the delay time of a CW unkey. I was getting RF in the pan adapter wire I installed. 

Joe
KD2NFC 



On Apr 17, 2019, at 5:27 PM, Adrian Chadd <adrian@...> wrote:

hi!

I've noticed on my ubitx4 that when you key down for the first CW tone (when it transitions RX->TX and transmits a tone) I get some pretty hefty harmonics out before it settles down. Subsequent CW tones whilst TX is asserted is fine.

It shows up on an LED SWR meter as a quick, bright flicker before it settles in OK.

I'm running the stock firmware with a couple of other bugfixes (like changing LSB<->USB doesn't immediately reprogram in the correct VFO until you change frequency..)

Has anyone else seen this? Is this fixed in Ian's firmware? (I checked out the source code and I can't see anything obviously fixing TX<->RX timing or the order which oscillators are gated/programmed.) Or should I go and dig into it a bit myself?

Thanks!


-adrian

Re: next ubitx

Curt
 

Coils and toroids prewound? Sacrilege! Wait, some dear ladies did wind these for us.

Its a bigger chore to kit a 100w rig for the masses. Devices to cover all HF may cost more than a ubitx.

Enterprises for the ham market take careful targeting.  lets be glad we have several focusing on the low cost market.

Curt

Re: uBitx V5 Audio improvement

John Owens
 

Philip,
Where does the 470/10uf go across for audio improvement on the uBitx.
Thanks John Owens K6TVY

On 14 Apr 2019, at 2:32 PM, Philip <philip.g7jur@...> wrote:

I have found that a 470 ohm in series with the 10 uF, seems to work well.
Philip G7JUR

Re: next ubitx

Adrian Chadd
 

hi!

+1 on the comments.

Honestly though, if we had an ALC input to drive low to decrease TX gain and thus output, we could create our own power control loopbacks and SWR protection. It'd make 100W operation less.. crazy.

(I'd like to do this, but I'm still diagnosing the basics on the v4 board; I'd like the TX drive out to be clean before i feed it into an amp and waste more power..)


-adrian

Re: ubitx v5 down: IRF510 heatsink very hot immediately after turning on the radio #ubitx-help #ubitx

 

Hi Jerry,

This one has 5.0000 <- 4 decimal places and the cursor goes there!
6600 is like 5.000 only.

Mine came with firmware 1.6 and I updated it to 1.7. That stopped
the splash screen from showing when switched on via soft key.

When the amplitude cursor is moved using left/right buttons the
cursor moves one or two steps right and then disappears. Next
attempt it may or may not move.. sometimes the cursor will move
to the 4th decimal. Flakey IMHO. Should be fixed in the firmware
hopefully soon.

I connected the PC to the 6800 via USB and started the software
and asked it to upgrade and it did the needful.

The Tek AFG1062 is a delight to use in comparison!
But the price !!!

Raj

At 17-04-19, you wrote:
Raj,

In what way is the FY6800 a bit flakey to operate?
I'm very curious, as am on the verge of buying one.

Re: ubitx v5 down: IRF510 heatsink very hot immediately after turning on the radio #ubitx-help #ubitx

Tom, wb6b
 

Hi,

Here is a photo of the inside of my signal generator, model JDS6600. 

When I lowered the output voltage I heard a relay click at about 6.0 and 0.6 volts. 

If you look at the photo you can see the part numbers have been ground off several of the ICs. This is the second thing I've received from China in the last month where they did this. I wonder if this has something to do with the recently enacted tariffs of if they are afraid someone in China will clone a counterfeit copy of their product.

Not so bad in this case, but they also did this to the main IC of a digitally controlled RF attenuator I received. That is very problematic, as I needed the part number to reliably establish the actual characteristics of the attenuator. Fortunately it is the low frequency side of the response curve I need to establish, I will be able to accurately measure that myself.

Tom, wb6b


Re: Trial to control CW power (and reduce harmonics as a result) by unbalancing the 2nd mixer #ubitx

John (vk2eta)
 

It now works, and works well.

Thanks Jerry, the different topology between T2 and T4 was the key issue with the unwanted unbalancing. I can't see why, but that is exactly what is happening.

So the successful modification to get the clock #1 mixer to unbalance on CW key down is the following:

1. Re-wire the T4 transformer input and output as per T2. That means as Jerry said to "... cut traces to T4 pins 3,5 and 6.
Swap them so T4 pins 3,5 are in from R47, pin 6 is out to C211."

2. Disconnect (cut trace) from R105 to the common connection of C10, R27 and T2 (3,5).

3. Connect via a wire the disconnected side of R105 to the common connection of T4 (3,5), C211.

I used an audio shielded cable, and passed the wire under the board by drilling two small holes next the two connection points to ensure minimal pick-up of RF.

 Pictures of R105 trace cut and wire to T4. (partially obscured by the hot melt glue on the toroids as I use my rig /P and /PM).


Picture of T4 traces swapped and cable from R105. (The line from the yellow toroid is a hot melt glue filament, not a wandering wire..hihi)



4. Change the software to, when in TX CW mode, disable clock #0, generate a clock #1 at “SECOND_OSC_USB” - “usbCarrier” = 45Mhz (+ or -) and clock #2 at (that same 45Mhz signal + target Tx frequency).


The difference in signal strength between key-up and key-down as seen on a control receiver is from way below S0 to S9+20dB or so, giving a dynamic range of over 70dB (indicative value in light of the basic test method).

The output power in CW mode can now be controlled finely by shifting the 45MHz clock slightly along the slope of the Xtal filter. For example I go from 14W max to between 1.5 and 2 watts by shifting the clock #1 frequency by 30Khz on the 20M band. On the 10M band, I need a shift of about 10Khz to reduce the 8 watts out to the same level.

Now to a bit of programming and I have full control of SSB as well as CW power across bands. Great for my built-in ATU.

If someone with a spectrum analyzer could check the implications for the harmonics and spurs that would be a plus. I would expect in CW mode that the harmonic for 80, 40 and 30M bands would reduce, but some spurs to appear since we have the beat of two clocks now.  If there is interest I can modify Farhan's code to match that modification (or publish some code snippets).

By the way, before I did the mod above, I also tried to put a trim-pot between R105 / Ground / slider to T4 (3,5) and even when turned all the way to zero (slider to ground) it would still constantly unbalance the clock #1 mixer. So the change in topology as described above is the only way I could get it to work as intended.

73, John (VK2ETA)

Re: next ubitx

Jerry Gaffke
 

If you want to electronically adjust TX power out on the uBitx, talk to John, VK2ETA

He's got that working with no hardware mods for SSB:
    https://groups.io/g/BITX20/message/45781
and now with some minor mods for CW:
    https://groups.io/g/BITX20/message/67981
    
Jerry, KE7ER


On Wed, Apr 17, 2019 at 07:49 PM, Adrian Chadd wrote:
Honestly though, if we had an ALC input to drive low to decrease TX gain and thus output, we could create our own power control loopbacks and SWR protection. It'd make 100W operation less.. crazy.
 
(I'd like to do this, but I'm still diagnosing the basics on the v4 board; I'd like the TX drive out to be clean before i feed it into an amp and waste more power..)
 
 
-adrian