Re: v5 12m/10m Spectrums

ronmhauser@...

Hi Curt.  I had to prove it to myself using a spreadsheet when I started reading these, dBm or dBV doesn't matter when comparing peaks within one spectrogram.  Here's my math proof using the peaks from the file 24895_30mWpp_3W.jpg.  All the peaks in the spectrogram are relative to one volt.  The instrument doesn't know the input impedance of the system so it can't do the calculation to change them to dBm.  But all the peaks are using the same input impedance, whatever it is, so it doesn't matter.  The difference between peaks in dB is what we care about, looking for -43dB down from the fundamental.  Right?  For the record the transmitter is terminated in a 50 ohm dummy load and the cable to the instrument is also terminated in 50 ohms ... but mathematically it doesn't matter it's the same impedance at for both peaks in the calculation.

73
--Ron
K0EIA

Re: CW key sticking with Nextion LCD

I didn't follow the link but You might try a torrid on the orange line and/or between the raduino and nextion.

Re: v5 12m/10m Spectrums

Curt

My concern is whether we are measuring a power ratio or a voltage ratio - I am suspicious we could be measuring the latter -- see

https://en.wikipedia.org/wiki/Decibel#Voltage

I am thinking that if the ubitx is loaded at 50 ohms that the instrument may be taking valid data.  But perhaps a conversion to power ratio is necessary.  40 dB in voltage corresponds to an amplitude ratio of 100, while in power it is 10000.  yes note this can be the difference between having spurs at - 43 dB or - 23 dB when the unit is power!

See if you instrument offers a tutorial on this.  I am thinking that even though voltage is being sensed, possibly the instrument knows how to do the conversion to power (??).

As I possess a ubitx (v4) with spurious around -33 to - 35 dBc in the upper bands on SSB - I was hoping your v5 to be much better, but I don't want us to jump to that conclusion without careful evaluation.  [The greater news - my box is compliant on SSB up to 17m, and now good on CW - 'just' with a relay transplant to add a second set of relays on a daughter board].

Curt

Re: v5 12m/10m Spectrums

ronmhauser@...

Well, the AD2 is really a (software defined digital) scope with FFT ... so the front end is a scope front end, the probes are high impedance voltage input.  Therefore the display is relative to voltage, not power.  I can't choose dBm ... BUT ... the measurement between the fundamental and the harmonics and spurs are relative, they are dB down from fundamental.  Changing the reference changes the scale on the left, but not the difference between the peaks.  (Unless I am doing the decibel math wrong, which is possible).

On mine -- on 12m -- with mike gain and RV1 turned down -- I'm calling it FCC compliant with all peaks 43dB down from the fundamental on 12m, either SSB or CW.

73
--Ron
K0EIA

Re: CW key sticking with Nextion LCD

Joe Puma

Thanks Sam!

Sent from Mail for Windows 10

From: BITX20@groups.io <BITX20@groups.io> on behalf of Sam Tedesco <stedesco619@...>
Sent: Wednesday, April 10, 2019 9:25:17 AM
To: BITX20@groups.io
Subject: Re: [BITX20] CW key sticking with Nextion LCD

Re: Microphone choices

I bought one for my bitx40 they work out very nice. I take the element out and put it in a mini mic.

http://www.jlielectronics.com/microphones/com-mic-jli-52b/
--
David

N8DAH
Kit-Projects.com

Shop is open!

Re: CW key sticking with Nextion LCD

Sam Tedesco

Re: CW key sticking with Nextion LCD

Sam Tedesco

I'm on v3, also. I tried looking for the original post, but couldn't find it. Anyway, your descriptions sounds about right. I thought it was odd back when I tried it for the first time...I have a few ver 3 boards and have used it on every one. I'll keep looking for the original info.

Re: Microphone choices

MVS Sarma

Even if one is rich, i suppose that there is no point in investing in mics that zerve high end systems for ham use. We dont really need more than 0.3 to 3Khz at the maximum

Regards
Sarma vu3zmv

On Wed, 10 Apr 2019, 5:04 pm iz oos <and2oosiz2@... wrote:

If you can't afford a Behemoth microphone (hi hi) you may try high sensitivity (around - 24db) electrec elements you may find at large vendors (Mouser etc). I opted for dynamic elements (not for karaoke) plus a homemade vogad compressor.

Il 10/apr/2019 13:22, "David - CA3DPV" <david.parra@...> ha scritto:
My two cents...

First I've tried with a karaoke mic and a audio console
Good: I get 10W of power without effort, talking quietly
Bad: The signal transmitted is extremely low pitch (very dificult to copy).

Now I use a PC mic (purchased for a few bucks). PTT is a button installed on it.
Good thing: It's a very cheap and small desk microphone (3 USD),
Bad thing: It's a low gain mic, get 4 or 5 watt only @40m

Re: Microphone choices

iz oos

If you can't afford a Behemoth microphone (hi hi) you may try high sensitivity (around - 24db) electrec elements you may find at large vendors (Mouser etc). I opted for dynamic elements (not for karaoke) plus a homemade vogad compressor.

Il 10/apr/2019 13:22, "David - CA3DPV" <david.parra@...> ha scritto:
My two cents...

First I've tried with a karaoke mic and a audio console
Good: I get 10W of power without effort, talking quietly
Bad: The signal transmitted is extremely low pitch (very dificult to copy).

Now I use a PC mic (purchased for a few bucks). PTT is a button installed on it.
Good thing: It's a very cheap and small desk microphone (3 USD),
Bad thing: It's a low gain mic, get 4 or 5 watt only @40m

Re: Microphone choices

David - CA3DPV

My two cents...

First I've tried with a karaoke mic and a audio console
Good: I get 10W of power without effort, talking quietly
Bad: The signal transmitted is extremely low pitch (very dificult to copy).

Now I use a PC mic (purchased for a few bucks). PTT is a button installed on it.
Good thing: It's a very cheap and small desk microphone (3 USD),
Bad thing: It's a low gain mic, get 4 or 5 watt only @40m

Re: Poor mans spurs and harmonics check with uBitxandcommercial radio

Joe Puma

Yes the uBitx might have some flaws but not hard to find issues with other radios or how a ham is using it, mods, running power, etc. There are a lot of aging radios out there, my 840 is of the latest breed and I was told when I bought it a year+ ago that the owner had recently purchased and  went SK shortly after.  I reviewed the alignment procedure quite a bit but I don’t have the right test equipment to run through the procedures and I’ve been firm on not using the radio a guinea pig, that’s what the uBitx is for.

Joe

Sent from Mail for Windows 10

From: iz oos
Sent: Wednesday, April 10, 2019 2:51 AM
To: BITX20@groups.io
Subject: Re: [BITX20] Poor mans spurs and harmonics check with uBitxandcommercial radio

:) I think the TX of the ubitx has been the most tested, loved and blamed by hams in history. Also because it should be assumed that commercial ones should have no basic issue in terms of harmonics and spurs. However mods in commercial rigs are not that infrequent and the consequences of these should also be thoroughly tested. And of course some might always say, yeah the 840 is an old radio that needs to be 'aligned', you would better off buying a new rig!

Il 10/apr/2019 08:01, "Joe Puma" <kd2nfc@...> ha scritto:

Looks like the ubitx screenshot didn’t get attached properly, here they both are again for comparison.

Sent from Mail for Windows 10

From: Joe Puma via Groups.Io
Sent: Wednesday, April 10, 2019 1:51 AM
To: BITX20@groups.io
Subject: [BITX20] Poor mans spurs and harmonics check with uBitx andcommercial radio

Hi,

I just did a quick comparison test between my ubitx and Yaesu ft-840 radio.  I used a SDR on a laptop with a up converter, the SV1AFN with a 200mhz LO. I had a multiband antenna on it from a Yaesu XV-7R, its tuned to receive AM broadcast band. I was using Touchstone and scanning from 200-230mhz (0-30mhz). The ubitx was transmitting around 12watts,  the FT-840 at 10watts but with CW key down and they were both transmitting on antenna EFHW antenna.

The ubitx show two spikes that the FT-840 does not show  at all but its almost similar with other spurs. The signal appears stronger with the FT-840 but its spurs are relatively similar to ubitx. Actually the ubitx spurs seem to be relatively less from main signal when compared to FT-840.

I have to find a local ham club with some gear to test the uBitx and maybe the FT-840 while I’m at it. 😊

This is a no TX baseline.

Joe

KD2NFC

Sent from Mail for Windows 10

Re: uBitx V5 Audio improvement

Jim Tibbits

Attached couple of mods I've been using ...One variable audio filter and one mod Re 386 ...
The 386 shows what I measured on the ic with a 10 uF cap pin 1-8 ...flat from near dc to daylight ..What I heard was LOTS of wideband noise ..Cut it with the installed L/C filter ... then installed the op-amp variable filter ..found I did not need the 386 bandpass mod with the variable filter ...both mounted on same board and plugged into U1 socket on V3 board ...dono what would be needed to adapt to ver 4/5

Jim

On Tue, Apr 9, 2019 at 9:26 PM Ashhar Farhan <farhanbox@...> wrote:
Exact!

On Tue 9 Apr, 2019, 12:09 PM Jerry Gaffke via Groups.Io, <jgaffke=yahoo.com@groups.io> wrote:
For LM386 gain that is flat across 300 to 2300 Hz
and is more than 26dB (no cap) but less than 46dB (10uF cap),
this is done by adding a resistor in series with that 10uF cap.

Re: Poor mans spurs and harmonics check with uBitx andcommercial radio

iz oos

:) I think the TX of the ubitx has been the most tested, loved and blamed by hams in history. Also because it should be assumed that commercial ones should have no basic issue in terms of harmonics and spurs. However mods in commercial rigs are not that infrequent and the consequences of these should also be thoroughly tested. And of course some might always say, yeah the 840 is an old radio that needs to be 'aligned', you would better off buying a new rig!

Il 10/apr/2019 08:01, "Joe Puma" <kd2nfc@...> ha scritto:

Looks like the ubitx screenshot didn’t get attached properly, here they both are again for comparison.

Sent from Mail for Windows 10

From: Joe Puma via Groups.Io
Sent: Wednesday, April 10, 2019 1:51 AM
To: BITX20@groups.io
Subject: [BITX20] Poor mans spurs and harmonics check with uBitx andcommercial radio

Hi,

I just did a quick comparison test between my ubitx and Yaesu ft-840 radio.  I used a SDR on a laptop with a up converter, the SV1AFN with a 200mhz LO. I had a multiband antenna on it from a Yaesu XV-7R, its tuned to receive AM broadcast band. I was using Touchstone and scanning from 200-230mhz (0-30mhz). The ubitx was transmitting around 12watts,  the FT-840 at 10watts but with CW key down and they were both transmitting on antenna EFHW antenna.

The ubitx show two spikes that the FT-840 does not show  at all but its almost similar with other spurs. The signal appears stronger with the FT-840 but its spurs are relatively similar to ubitx. Actually the ubitx spurs seem to be relatively less from main signal when compared to FT-840.

I have to find a local ham club with some gear to test the uBitx and maybe the FT-840 while I’m at it. 😊

This is a no TX baseline.

Joe

KD2NFC

Sent from Mail for Windows 10

Re: Poor mans spurs and harmonics check with uBitx andcommercial radio

Joe Puma

Looks like the ubitx screenshot didn’t get attached properly, here they both are again for comparison.

Sent from Mail for Windows 10

From: Joe Puma via Groups.Io
Sent: Wednesday, April 10, 2019 1:51 AM
To: BITX20@groups.io
Subject: [BITX20] Poor mans spurs and harmonics check with uBitx andcommercial radio

Hi,

I just did a quick comparison test between my ubitx and Yaesu ft-840 radio.  I used a SDR on a laptop with a up converter, the SV1AFN with a 200mhz LO. I had a multiband antenna on it from a Yaesu XV-7R, its tuned to receive AM broadcast band. I was using Touchstone and scanning from 200-230mhz (0-30mhz). The ubitx was transmitting around 12watts,  the FT-840 at 10watts but with CW key down and they were both transmitting on antenna EFHW antenna.

The ubitx show two spikes that the FT-840 does not show  at all but its almost similar with other spurs. The signal appears stronger with the FT-840 but its spurs are relatively similar to ubitx. Actually the ubitx spurs seem to be relatively less from main signal when compared to FT-840.

I have to find a local ham club with some gear to test the uBitx and maybe the FT-840 while I’m at it. 😊

This is a no TX baseline.

Joe

KD2NFC

Sent from Mail for Windows 10

Poor mans spurs and harmonics check with uBitx and commercial radio

Joe Puma

Hi,

I just did a quick comparison test between my ubitx and Yaesu ft-840 radio.  I used a SDR on a laptop with a up converter, the SV1AFN with a 200mhz LO. I had a multiband antenna on it from a Yaesu XV-7R, its tuned to receive AM broadcast band. I was using Touchstone and scanning from 200-230mhz (0-30mhz). The ubitx was transmitting around 12watts,  the FT-840 at 10watts but with CW key down and they were both transmitting on antenna EFHW antenna.

The ubitx show two spikes that the FT-840 does not show  at all but its almost similar with other spurs. The signal appears stronger with the FT-840 but its spurs are relatively similar to ubitx. Actually the ubitx spurs seem to be relatively less from main signal when compared to FT-840.

I have to find a local ham club with some gear to test the uBitx and maybe the FT-840 while I’m at it. 😊

This is a no TX baseline.

Joe

KD2NFC

Sent from Mail for Windows 10

Re: uBitx V5 Audio improvement

Ashhar Farhan

Exact!

On Tue 9 Apr, 2019, 12:09 PM Jerry Gaffke via Groups.Io, <jgaffke=yahoo.com@groups.io> wrote:
For LM386 gain that is flat across 300 to 2300 Hz
and is more than 26dB (no cap) but less than 46dB (10uF cap),
this is done by adding a resistor in series with that 10uF cap.

Re: Microphone choices

Kelly Mabry

Hi Mike,  a lot of ideas abound; some are repurposed cb microphones,  some are home brewed with what's in the kit, I ordered a Uniden BC645 4-Pin Microphone for CB Radios, electret mic, going to wire the 4 pin panel plug to fit the microphone.  Others have changed out the 4 pin to match their 8 pin QRO rigs. I would dig around the ubitx.net site and hfsignals.com ... Somewhere I  remember that a dynamic mic needs a tantalum cap on the input. But in reality there are even 3d printed mic housings to assemble a mic. Check out https://shop.kit-projects. They have mics and paddles!
73,
Kelly K5AID

Microphone choices

Michael Goins, k5wmg <wmgoins@...>

Looking to use my BITX on SSB and cw and trying to figure out a good mike for it, either hand or desk. Will likely take to Costa Rica later in the year and possibly leave there. Suggestions or where to look for more information?

Re: CW key sticking with Nextion LCD

Joe Puma

Which bitx are you using. I have uBitx and R52 is near audio predriver and its a 2n3904. How do I do this on a uBitx v3. I guess this is what we call a carrier burst?

Joe

KD2NFC

On Apr 9, 2019, at 12:34 PM, Sam Tedesco <stedesco619@...> wrote:

Hi Joe,

There was a blocking diode fix on r52 that fixed all of my cw issues. I'm going off of memory...but, I lifted r52, on side towards 2822 chip, add diode in series...cathode down to board. I run my delay 450-500