¿ªÔÆÌåÓý

  1. BITX20
  2. Messages
Expanded Topics Messages Polls
Date
Re: Modulated CW, A2A transmission

 

there is no carrier so it's not MCW I thought the same thing before and did a looking... Poke around google for MCW and ACW is what i think it's called.

On Thu, Apr 6, 2017 at 1:51 PM, Jack Purdum via Groups.Io <econjack@...> wrote:

I just read through the FCC regs and section?¡ì97.305?on the types of transmissions that are allowed on various bands. It appears to me that Modulated CW (A2A), which some have suggested here for the BITX40, it not allowed on frequencies below 6M. Any experts out there?


Jack, W8TEE
Re: Help!

Jack Purdum
 

Can you give more details? Since the IDE is free, why not upgrade?

Jack, W8TEE


From: Nick Tile <juggie@...>
To: [email protected]
Sent: Thursday, April 6, 2017 2:00 PM
Subject: Re: [BITX20] Help!

I'm getting some weird compile errors based on it not liking long integers I think - currently using 1.60 - suspect that I need to upgrade the IDE ... ?

Nick, G8INE
Re: Modulated CW, A2A transmission

 

from the wiki article?
Modulated CW (A2A)

MCW can be transmitted from any common amateur radio transceiver in AM or FM mode with audio input from an audio tone oscillator or equivalent audio source.?MCW is not allowed in the United States on??frequencies lower than?, or between 219 and 220?MHz, as it is a very inefficient use of radio spectrum. When the amateur radio transceiver is in SSB mode, the resulting modulation is J2A or J2B and therefore not MCW by definition.

(emphasis is mine.)

Larry
KB3CUF

On Thu, Apr 6, 2017 at 1:51 PM, Jack Purdum via Groups.Io <econjack@...> wrote:

I just read through the FCC regs and section?¡ì97.305?on the types of transmissions that are allowed on various bands. It appears to me that Modulated CW (A2A), which some have suggested here for the BITX40, it not allowed on frequencies below 6M. Any experts out there?


Jack, W8TEE
Re: SD Card [EEPROM life/wear out]

Pavel Milanes Costa
 

¿ªÔÆÌåÓý

Hi, let me please kill some spooky ghosts now.

The eeprom inside the MCU has in deed a limited write count, in the order of 100k before it get start failing, that's datasheet facts, and please observer they always write "at least".

Practice tells that they are about 1 Million at least before the first sign of corruption () and here the issue for this particular subject [spoiler: about 4 to 6 million writes before corruption] () and here you can find more insight from the manufacturers it self, they claiming about 8 Million writes before corruption () and with aggressive procedures...

Never the less, around Arduino IDE 1.6.9 the eeprom procedures was improved with a new function called: update; it took a little longer (read, compare and write only the difference, if there is one) but it can make you win a few years of eeprom work.

Stop worrying about eeprom life people !!! USE IT.

With moderate updates (~ 10 minute each)? and the "update" trick it can assure years of joy with you homebrew projects.

Do your math:

Let's assume 2 Million writes before death as a guess, and at least 8 hours of use daily, with the extreme scenario of a full save every time:

8 hours @ 10 minute save intervals per day = 48 writes per day, then one year = 17 520 saves (17.5k)

With that scenario estimated life time is around 114 years !!! (2M/17.5k)

Even at the standard factory writes-before-corruption of 100k it will took 5.7 years to wear it down.

Even in the case of eeprom corruption of the lower eeprom mem [do you really use the whole eeprom?] you can code the sketch to use the next page in the eeprom and it will WORK again for another period...

Move yourself 5.7 years into the future... [me looking to the magic sphere] :

luckily the Arduino UNO/Nano/Mini will be obliterated by another cheap and yet unknown homebrew tech [SMT32/Blue pill?] or it will cost less than a beer.

73 Pavel CO7WT.

El 04/04/17 a las 18:09, howardmsmall escribi¨®:

From earlier posts I am led to believe that writing frequencies too often to the eeprom will shorten its life considerably. I had in mind the possibility of storing frequencies ad hoc which coukd then be too frequent.


Howard, VK4BS
Re: Help!

 

I'm getting some weird compile errors based on it not liking long integers I think - currently using 1.60 - suspect that I need to upgrade the IDE ... ?


Nick, G8INE
Modulated CW, A2A transmission

Jack Purdum
 

I just read through the FCC regs and section?¡ì97.305?on the types of transmissions that are allowed on various bands. It appears to me that Modulated CW (A2A), which some have suggested here for the BITX40, it not allowed on frequencies below 6M. Any experts out there?


Jack, W8TEE
Re: Quick turn around

MM0DHY
 

Another quick delivery to Scotland


Ordered 22 March arrived 4 April


BITX40 Version 3 with Radino N3 - 803

The learning begins!

Adrian

MM0DHY
Re: PTT pop hack

Baruch Atta
 

"... Power the audio stages directly by connecting 12V line to the junction of R111, R113 and D18.
Now you will hear your own voice during TX and we need to mute it..."

Is that so bad - to hear your own voice during transmission?? Would this alone reduce or eliminate the pop on keying the transmitter?
Also, this could be a nice sidetone monitor when injecting a tone into the mic when attempting to use the BitX for CW?

I put the BitX away for awhile until I could find a solution to the popping!? I use earphones exclusively, no speaker, and the pop sounds like a bolt of lightning to me.?

thanks
Joe W3TTT




On Wed, Mar 8, 2017 at 3:03 AM, Raj vu2zap <vu2zap@...> wrote:
No problem Simon,

Now its good time at Melbourne for a beer or to try another hack on bitx40.

Try this:

1. Power the audio stages directly by connecting 12V line to the junction of R111, R113 and D18.

Now you will hear your own voice during TX and we need to mute it.

2. Take a 2N7000 or similar and connect SOURCE to ground, DRAIN to the top of the volume control (M1/M2).
feed the TX 12V through a 10K or nearby value to the gate.

This should mute the amp during TX.

If this works for you then remove the diode D18!

Caveat: I have not tried it as I am at the coffee farm this week. Itching to get back to my board but it will be Monday next!
While in TX mode some RF might get into the amp stage and be just as annoying.
Then we have to work more on that! A 0.01 across the volume control might fix this if it happens.

Cheers
Raj
Re: I think this is absolutely amazing!

 

I find myself in agreement with Richard Spohn. I get really excited about trying circuit and firmware mods, and actually doing something on my own, rather than just plugging in a store-bought unit and keying the mic.? I realized from the beginning that this radio would require some tweaking and customization, and that's all part of the fun!
Re: No sound from bitx 40

 

If you are not getting even a hiss with the volume control at maximum, then something is wrong in one of the two audio amplifier stages. ?Check for 12v to pin 6 of the LM386 at U1. ?Should see several volts at the node between Q16 and R112 (the Q16 collector). ?Check the connection out to the speaker, make sure the speaker is in working condition. ?


Compare your DC voltage readings using a voltmeter with those in this file ??/g/BITX20/files/K7AGE/BITX40%20Voltage%20Measurments.pdf? from this post ?/g/BITX20/message/23583?

Listening in at the volume control is a good idea, but you might not hear much hiss without the gain from U1.

Jerry, KE7ER


?

On Thu, Apr 6, 2017 at 07:33 am, John T P wrote:

Dear OM,

I baught one of Farhan ' s Bitx40 assembled PCB last ham convention in Always, Ernakulam. I assembled wired properly in a box . Connected with 12V regulated power supply.
But no sound.
I tried even to take out audio from volume control. Still no signal.
How can I solve it?

Any clue?

73ees

VU2JON
John

English out

?
Re: Help!

Andrew Whaley
 

The Arduino IDE makes it easy. You just load up the sketch and click the upload button and it compiles it and transfers it to the device via the USB cable. Practice this a few times before you start replacing it on the PCB.
Re: Help!

[email protected]
 

Thanks for replies,I am pretty sure the nano is blown.

Ive ordered a replacement,Ive never done anything with programmeing.So I suspect I ll be doing a lot of reading.The scary thing is I still dont know what I did to blow it.I think at some point I must have cut through a lead while power was on.Perhaps thats it.I did not cut through more than one wire at a time. That will teach me to be tidy.I was really impressed with receiver while it lived.It compared favourably with a funcube dongle. 73s
Done got it!

Darrell Collins
 

WA7DSV ordered 3-9-17

ship 3-17-17

Delivered 4-3-17


S/N N3 757 (Check mark)
Re: R136 RF Drive Control - how to set?

 

John

Thanks, glad that the antenna works.

Randy, K7AGE

On Wed, Apr 5, 2017 at 11:12 PM, John Smith via Groups.Io <johnlinux77@...> wrote:

I feel bad about making everyone run out of the room before Randy K7AGE got to read an answer to his question. He's a pretty good Youtuber. His video on a 2 Meter out door ground plane antenna has worked wonderfully for me. And I will always tell others new or rebuilding hams, the copper ground wire ground plane antenna is very hard to beat.

So thanks for that Randy, I can work repeaters all around and outside of the Greater Oklahoma City metropolitan area. It's Outdoors at about 20 feet high, crowning the apex of my 40 meter inverted vee.
No sound from bitx 40

 

Dear OM,

I baught one of Farhan ' s Bitx40 assembled PCB last ham convention in Always, Ernakulam. I assembled wired properly in a box . Connected with 12V regulated power supply.
But no sound.
I tried even to take out audio from volume control. Still no signal.
How can I solve it?

Any clue?

73ees

VU2JON
John

English out

Re: Raduino clicks

Pavel Milanes Costa
 

Yes,

I tested the DK7HI solution and it works, I then came up with a entirely click-less solution (and a really tiny code) in my main project, see , specially the file fd-si5351.ino for the entire code.

This code has a lot from different sources, mainly the QRPLabs examples and the tricks from DK7HI, it's free software, you are free to copy/user/distribute it.

But it has a dark side, it works for short spans of freq, as I have tested (little testing) it can unlock the PLLs if you move away more than 1Mhz (far safe for lower HF bands) but I will recommend to make a "reset" every 500Kc of movement to be safe (function Si5351_resets()) and that will produce a click every time you reset it.

I can pack this in an arduino lib if needed... any beta testers for such a lib?

73 Pavel CO7WT.

El 06/04/17 a las 00:27, John Backo via Groups.Io escribi¨®:
Note this from DK7IH (via CO7WT). I have not checked the code, but this is the probable source of the
"clicking" in the Raduino. See the CO7WT sketch for more information.

"Some authors join the two functions (PLL definition and multisynth definitions) in the set_freq() function. I tried to avoid this because the code will be faster if you only set the PLLs once and afterwards just modify the frequency. Another idea that should be avoided is to switch off the PLLs during reprogramming the frequency. Unpleasant short-term absence of receiving signal is an outcome of the switch-off strategy. I leave the Pll running the whole time."

john
AD5YE
Re: Quick turn around

 

I'd like to update the two i've ordered. I ordered on 2/14/17 - shipped 2/25/17
Re: Quick turn around

 

For attention of Randy? , K7AGE

BITX40 version 3 with Raduino???? N3-837V
Ordered?? 23 March???????? Arrived? 6 April? in north of Scotland

Well packed in bubble sheet? ;?? 1 yellow toroid wound loosely but not broken
When radio works well ,shall secure toroid with epoxy.

Enclosure with handle ordered from Banggood on ? 1 April (no joke) also arrived 6 April . ?
But radio will be initially fitted on a piece of plywood with all external components to learn/experiment and add features like audio compression ,AGC ,S-meter? etc

Climbing the (steep?) learning curve can begin .

Frank?? ,??? GM0CSZ / KN6WH?????? in IO87AT


On Thu, Apr 6, 2017 at 2:25 AM, John Backo via Groups.Io <iam74@...> wrote:
The serial number is N3-476.

john
AD5YE
Re: raduino v1.05 released: kill the 7199 birdie

Andrew Whaley
 

It's a standard board although I have 2 mods :-

everything else is vanilla as it came.

It was with a dipole antenna (not quite tuned) routed through an SWR meter and using headphones as audio out.
Re: raduino v1.05 released: kill the 7199 birdie

 

Andrew,

The default drive strength is 2mA.

just curious:
under what conditions did you try the different drive levels?

Assumed (default) condition is a standard unmodified BITX40 board:
- VFO on the low side of the IF (so 5Mhz, not 19MHz)
- L4 removed
- caps C91 and C92 not removed

73, Allard PE1NWL
91521 - 91540 of 116174