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Re: I find the Transmit audio is a bit muffled has anyone else found this?

 

John Smith write
>I just now performed the Peter Parker improved audio hack with a 10 - 40pf trimmer cap and observed the following.
>Before soldering it on I set it for approx 27pf, and heard a noticeable higher pitched static when I turned it on.
>I tuned in a QSO? and adjusted for optimum tonal quality. This was looking familiar.
>I loaded an WebSDR page and transmitted while adjusting the trimmer cap. I could hear my voice pitch go up
>and down like I was tuning the frequency around. Then I realized how this was looking familiar. It was providing
>the same results as calibrating the frequency offset. The band is currently dead, and I can't tell how much my
>calibrated offset has changed with this BFO tuning hack right now.?Does this make sense to anyone?
>Is this another way of doing the same thing with the calibration function?

The short answer is no. ?While there is interaction between the carrier oscillator frequency (which this mod changes) and the calibration or offset setting in the DDS VFO but they are very different adjustments.?

It is essential to get the relationship between the BFO crystal and the crystal filter bandpass right. ?This ensures punchy audio that's readable when the signal is weak. And people won't be saying your audio is muffled, thin or they have difficulty tuning you in. ?The carrier oscillator setting determines the tx and rx audio bandpass and is more complex than simply being on or off frequency. Set it for optimum transmitted audio and ignore that the frequency display is different on the rig you're aligning and your test receiver. ?The setting that is right for tx audio should also be right for rx audio as the carrier oscillator/BFO and xtal filter are shared.?

Once happy with the audio audio bandpass characteristics you can adjust the offset setting in the DDS to match the BFO frequency so your display lines up with other stations. ?You can usually tell this without any special measuring since most stations on 7 MHz operate on exact multiples of 1kHz. So if all stations are tuned in well when tuning in 1 kHz steps with your DDS you should be right.?
Re: I find the Transmit audio is a bit muffled has anyone else found this?

OZ9AEW
 

when you made that mods you have changed your BFO-Freq, if you look inside the Raduino schetch you fin this line
?#define bfo_freq (11998000UL)
if you find a counter you will have the right Freq for that line
Re: I find the Transmit audio is a bit muffled has anyone else found this?

 

I just now performed the Peter Parker improved audio hack with a 10 - 40pf trimmer cap and observed the following. Before soldering it on I set it for approx 27pf, and heard a noticeable higher pitched static when I turned it on. I tuned in a QSO? and adjusted for optimum tonal quality. This was looking familiar. I loaded an WebSDR page and transmitted while adjusting the trimmer cap. I could hear my voice pitch go up and down like I was tuning the frequency around. Then I realized how this was looking familiar. It was providing the same results as calibrating the frequency offset. The band is currently dead, and I can't tell how much my calibrated offset has changed with this BFO tuning hack right now.

Does this make sense to anyone? Is this another way of doing the same thing with the calibration function?
Re: Baofeng microphone mod for BITX

Joe Puma
 

¿ªÔÆÌåÓý

It showing you where the push to talk connections are which is basically the grounds of both mic and speaker connections that are connected together when you press the push to talk. So yeah basically pressing the push to talk will combine the mic ground and speaker ground. I am not sure if that will cause conflict in the radio.?


Sent from my iPhone

On May 28, 2017, at 5:09 AM, DJ4MU <pbepler@...> wrote:

Despite the posted diagram i'm still not sure how to wire up the unmodified Baofeng mic to the Bitx.

the speaker connections seem obvious, with ground on the sleeve of 2.5mm and other speaker connection to tip.

the mic + connection seems fairly obvious too , on the ring of the 3.5mm.

But where are the mic - and PTT wires from the Bitx connected, and do they all use the same ground?

Which Bitx wire connects to the tip of the 3.5mm (v+) ?

<Bao_plug_Bitx.jpg>
Re: Bit of a problem?

 

¿ªÔÆÌåÓý

You connected the leads for the powersupply of the amplifier stage. I made this mistake initially.

Ron - PA3FAT

Sent from my iPhone

On 28 May 2017, at 21:59, Joe Puma <kd2nfc@...> wrote:

Find a websdr openwebrx close to you to see if you're getting out.?


Sent from my iPhone

On May 26, 2017, at 8:56 PM, Brian D. K2BRZ <kd2iog@...> wrote:

Yup, fixed the continuity problem on the coax jumper and still no reading on the SWR Bridge. The only other thing I can think of is that the unit is bad. Should the meter itself light up, does anyone know? I don't see anything that it should. I have an HT I can use to check but that is VHF, not HF.

How else can I verify if the radio has been damaged? No smoke has been let out and only minimal fiddling inside while doing mods, which I was sure to be careful with. Being that there isn't a signal going into the bridge, I am surmising the antenna probably isn't a problem for now. I don't have a dummy load to bias the radio, so I'm not sure if the very small fiddling I did with that may have done something.

73,
Brian, K2BRZ

Re: arduino ide

mike
 

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got there before me. CH340 drivers may work. I have FT232 UARTs in my Nano's


On 28/05/17 20:49, OZ9AEW wrote:

I expect you are going to use Arduino Ide for a Raduino-board !
then you have to find and install a driver for Ch340 % CH341 chip used in many clear Arduino Nano from China

Re: Bit of a problem?

Joe Puma
 

¿ªÔÆÌåÓý

You can also do a crew test by testing the AC out on the coacts line. ?Set your multi meter to high-voltage key up the mic and talk.?


Sent from my iPhone

On May 26, 2017, at 9:21 PM, Brian D. K2BRZ <kd2iog@...> wrote:

Yes, which is why I'm thinking it's the radio because nothing happens on the SWR bridge when I key the mic. Either that or the unit is defective.

My question is: How do I verify it is the radio with the problem?

Re: Bit of a problem?

Joe Puma
 

¿ªÔÆÌåÓý

Find a websdr openwebrx close to you to see if you're getting out.?


Sent from my iPhone

On May 26, 2017, at 8:56 PM, Brian D. K2BRZ <kd2iog@...> wrote:

Yup, fixed the continuity problem on the coax jumper and still no reading on the SWR Bridge. The only other thing I can think of is that the unit is bad. Should the meter itself light up, does anyone know? I don't see anything that it should. I have an HT I can use to check but that is VHF, not HF.

How else can I verify if the radio has been damaged? No smoke has been let out and only minimal fiddling inside while doing mods, which I was sure to be careful with. Being that there isn't a signal going into the bridge, I am surmising the antenna probably isn't a problem for now. I don't have a dummy load to bias the radio, so I'm not sure if the very small fiddling I did with that may have done something.

73,
Brian, K2BRZ

Re: arduino ide

OZ9AEW
 

I expect you are going to use Arduino Ide for a Raduino-board !
then you have to find and install a driver for Ch340 % CH341 chip used in many clear Arduino Nano from China
arduino ide

 

hi if i follow the steps for compiling and uploading for windows 7 ide all goes ok until i try tools/ports.
it only offers me com1 and com2 NOT usb

the upload obviously fails

terry gm4dso
Re: I find the Transmit audio is a bit muffled has anyone else found this?

Petry, Kevin
 

Thanks to the group for this thread, I just installed a 15-60 pf trimmer at C103 and adjusted for crisp receive audio and the transmit audio sounds great now!
Hoping for some contacts tonight on the 9PM get together around 7.277!
Kevin N8DLP
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Re: source for AD9850 DDS module for W8TEE TFT/VFO?

 

¿ªÔÆÌåÓý

Doug,

I actually received the "Right" AD98590 module pictured in the listing from these two Ebay sellers:

?

http://www.ebay.com/itm/172381520736

?

http://www.ebay.com/itm/180956144662

?

On the other hand, based on my? experience I? would not make a purchase from this seller:

suntekstore

?

73 & Happy BITXing

Bob? N0BHC
Re: BITX QSO Night, Sunday, May 28, 9pm Local Time, 7.277 MHz

 

My observation might be a confounding two cents, but here it goes. I don't hear the kilowatters other nights. We might be the QRMers stepping on their established nets or whatever. I think another night as well as other frequencies should be considered.

I plan to participate again tonight. de KG5KYJ, John, Oklahoma City.
I'll be working 7.178, 7.277, 7.285, as needed.?
Re: BITX QSO Night, Sunday, May 28, 9pm Local Time, 7.277 MHz

 

Just a reminder that the QSO night will happen this evening on 7277 in North America and 7177 elsewhere.? 9 pm local time.
Re: Jitter

 

here is a simpler way,?

1. change the band pass filter to 28 mhz. take the tap off the antenna end of band pass filter, modify the sktech to work on 28 mhz and you have the base of your transverter ready.

2. look around the vhf/uhf books and find stripline filter that makes a bandpass filter with just an etched FR4 board. no tuning really needed. now, add two 1N4148 as anti-parallel diodes, take an additional clock output of the raduino running at 202 MHz and use it as the LO (the anti-parallel mixer needs the vfo to be at half the LO frequency). you are on 70 cm!

3. to improve noise figure add a one dollar MAV-11 or MAR6, between the mixer and the band pass filter. Wow, now you are transmitting a full milliwatt

if this is all too cumbersome, just go and buy an RFM22B for three dollars. you don't know what that is? have you been living under a stone?

- f


On Sun, May 28, 2017 at 11:23 PM, David Woodward <kf4wbj2@...> wrote:

Yes I have one also...I made a moxon out of coat hangers and regularly work the fm sats...what I want is to work some ssb says like ao-7....
I have an rtl- sdr for receiving via sdr console v2.
I'm thinking of converting the BITX40 to 10 meters and using one of those Russian transverters for xmit...

On May 28, 2017 10:20 AM, "Jamie Rolfe" <j.rolfe8@...> wrote:
Hi David,?

I know.? These Bitx40 kits are excellent.? Glad you're having fun. It took me more time to make a box than to get on the air.?

If you want to get on 70cm cheaply I suggest the Baofeng uv-5r. They are an HT that run about $39. I've had mine for about 4 months and I've only had to charge it twice with stock battery. Accessories are super cheap online as well.?

I think I got mine from if I remember correctly.?

Cheers

Jamie VA3RLF?


topic search #w8tee

Jack Purdum
 

Good Idea...if I can remember it! I'm trying to limit the emails sent to the group. It should become less and less.

Jack, W8TEE


From: Ashhar Farhan <farhanbox@...>
To: [email protected]
Sent: Sunday, May 28, 2017 1:55 PM
Subject: Re: [BITX20] SMD orientation

Jack,

It might be easier for us to search for all the posts related to your board if we agree to suffix them the subject like with "w8tee vfo" or something. that way, the those how come in later will be able to search and read these posts sequentially.

just a suggestion, it will involve reposting the questions under a new subject line, but the categorization will be worth it.?

the other way is to add an easter egg '#w8tte-vfo' in the reply itself. those who search for this term will find these posts. it is a way to hashtag within the posts of this group.

- f

On Sun, May 28, 2017 at 11:13 PM, Jack Purdum via Groups.Io <econjack@...> wrote:
You should be ok with either, but the MAR-3SM is considered obsolete now.

Jack, W8TEE


From: Doug W <dougwilner@...>
To: [email protected]
Sent: Sunday, May 28, 2017 1:35 PM
Subject: Re: [BITX20] SMD orientation

Your BOM calls out a MAR-3SM+.? Most of what I am finding online is a MAR-3SM.? Do you know if the + designates anything important?? I didn't see anything that looked meaningful in the data sheets I could find.
thanks





Re: SMD orientation

 

¿ªÔÆÌåÓý

Doug,

?

The ¡°+¡± sign designates a part that is ¡°RoHS¡± (lead free) compliant.? Parts without the ¡°+¡± sign have the same functionality.

73,

Dale? K9NN

?

From: [email protected] [mailto:[email protected]] On Behalf Of Doug W
Sent: Sunday, May 28, 2017 1:35 PM
To: [email protected]
Subject: Re: [BITX20] SMD orientation

?

Your BOM calls out a MAR-3SM+.? Most of what I am finding online is a MAR-3SM.? Do you know if the + designates anything important?? I didn't see anything that looked meaningful in the data sheets I could find.
thanks



Re: SMD orientation

 

Jack,

It might be easier for us to search for all the posts related to your board if we agree to suffix them the subject like with "w8tee vfo" or something. that way, the those how come in later will be able to search and read these posts sequentially.

just a suggestion, it will involve reposting the questions under a new subject line, but the categorization will be worth it.?

the other way is to add an easter egg '#w8tte-vfo' in the reply itself. those who search for this term will find these posts. it is a way to hashtag within the posts of this group.

- f

On Sun, May 28, 2017 at 11:13 PM, Jack Purdum via Groups.Io <econjack@...> wrote:
You should be ok with either, but the MAR-3SM is considered obsolete now.

Jack, W8TEE


From: Doug W <dougwilner@...>
To: [email protected]
Sent: Sunday, May 28, 2017 1:35 PM
Subject: Re: [BITX20] SMD orientation

Your BOM calls out a MAR-3SM+.? Most of what I am finding online is a MAR-3SM.? Do you know if the + designates anything important?? I didn't see anything that looked meaningful in the data sheets I could find.
thanks



Re: Jitter

 

Yes I have one also...I made a moxon out of coat hangers and regularly work the fm sats...what I want is to work some ssb says like ao-7....
I have an rtl- sdr for receiving via sdr console v2.
I'm thinking of converting the BITX40 to 10 meters and using one of those Russian transverters for xmit...

On May 28, 2017 10:20 AM, "Jamie Rolfe" <j.rolfe8@...> wrote:

Hi David,?

I know.? These Bitx40 kits are excellent.? Glad you're having fun. It took me more time to make a box than to get on the air.?

If you want to get on 70cm cheaply I suggest the Baofeng uv-5r. They are an HT that run about $39. I've had mine for about 4 months and I've only had to charge it twice with stock battery. Accessories are super cheap online as well.?

I think I got mine from if I remember correctly.?

Cheers

Jamie VA3RLF?

Re: SMD orientation

Jack Purdum
 

You should be ok with either, but the MAR-3SM is considered obsolete now.

Jack, W8TEE


From: Doug W <dougwilner@...>
To: [email protected]
Sent: Sunday, May 28, 2017 1:35 PM
Subject: Re: [BITX20] SMD orientation

Your BOM calls out a MAR-3SM+.? Most of what I am finding online is a MAR-3SM.? Do you know if the + designates anything important?? I didn't see anything that looked meaningful in the data sheets I could find.
thanks


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