Date   

Re: the device is operational!

Richard Andrew Knack
 

Yeah, 7.055 is in our CW portion of the band, in the USA. Our voice mode segment is from 7.175 to 7.300 (General class license), and 7.125 to 7.300 (Extra class license).

Rich
KC8MWG



On Thursday, July 20, 2017, 9:32:53 PM EDT, Keith VE7GDH <ve7gdh@...> wrote:


I checked into the Aurora Net on 7055 KHz again
today (I don't believe our American friends can
operate voice there) and like yesterday, noticed
one station that was very strong and all but
un-readable. I confirmed today that it was a
station just 2 km from my location. I'm guessing
that he overloads the front-end and drives the
audio circuits into distortion unless the volume
is all but all of the way down. It will be
interesting to see how well the audio AGC deals
with it when it is added... or does someone
already have first-hand experience with stations
that strong?

I'll be in and out of the shack this evening,
but listening on 7277 KHz while I'm in... at least
until the AM broadcast station a couple of KHz
below there fades in and I get tired of listening
to the heterodyne. What... no notch filter? hi!
If I think of it, I'll throw a CQ out there at
the top of the hour and every 15 minutes.

--
73 Keith VE7GDH
CN88 Salt Spring Island, BC




Re: the device is operational!

Keith VE7GDH
 

I commented that...

The biggest issue I see so far is that SSB stations
sound a bit muddy and difficult to copy. I suspect
a BFO tweak might be needed.
WOW! I've replaced the tiny speaker with an outboard
2" speaker. The improvement in quality and level must
be heard to be believed. I no longer think that the
BFO needs tweaking. What an amazing radio the BITX40
is! Propagation might be a part of it, but I'm hearing
stations from Australia, New Zealand, Guam, New Guinea
and all over the US on 7163 KHz. One of the stations
(possibly Guam, but might have been arranging contacts
for Guam) picked up my call sign.

I've also extended the mic cable, so it's a lot
easier to use. I put the lid on the case for the
first time, but I've left the bail off as the
speaker and mic cables are temporarily exiting the
case through one of the holes used by the bail.
With the lid on, it will be a lot easier to move
around. If I get the 9:1 Un-Un finished, I'll cut
some wire for an end-fed and take the 20 ft
Wonder Pole outside with a battery tomorrow, but
I don't think propagation will be anything like
it is at this time of day... 02:30 Pacific time
at the time.

--
73 Keith VE7GDH


Re: the device is operational!

Keith VE7GDH
 

Just a picture with the lid on. The external speaker is over on the left. It was from a cell phone car-kit that was never used. The mic is for now in the plastic doohickey in the foreground. Now I don't half to lean all the way over to the radio to use the mic.



--
73 Keith VE7GDH


Wonder Pole...

Keith VE7GDH
 

Graham VE3GTC mentioned the Shakespeare Wonder Pole
recently. I have the 20 ft version here now! I haven't
tried it with an antenna yet, but I think it will do
a good job. I'm planning to use it with an end-fed wire
antenna and a 9:1 Un-Un with the BITX40 when portable.

https://www.amazon.ca/Shakespeare-Wonder-Pole-12-Feet-4-Piece/dp/B003D5VQ9S/ref=sr_1_1

--
73 Keith VE7GDH


Re: muddy audio

MVS Sarma
 

While using headset, perhaps one has to add 50 to 100 ohms series resistor to prevent headphone's  speaker elements from burning due to high audio power.


On Fri, Jul 21, 2017 at 12:18 PM, terryhugheskirkcudbright via Groups.Io <terryhugheskirkcudbright@...> wrote:
i always use headphones for both my bitx40 and my big rig.

i may be wrong but if your audio is good on transmit then your bfo is spot on - i would say leave it alone and use a headset

terry gm4dso




--
Regards
Sarma
 


muddy audio

terry hughes
 

i always use headphones for both my bitx40 and my big rig.

i may be wrong but if your audio is good on transmit then your bfo is spot on - i would say leave it alone and use a headset

terry gm4dso


Re: the device is operational!

Keith VE7GDH
 

I wrote...

I finally got it all put together...
(stuck in my outbox since yesterday, so
"this afternoon" is yesterday afternoon)

I installed Raduino V1.20 this afternoon,
but I haven't done any hardware mods yet. I
had to remove the tuning pot to get the USB
cable in there. Hopefully the 90 degree
extension cable when it shows up will fit
in there.

Then I made one more contact, checking into
the Aurora Net on 7055 KHz. The net control
station said I was "strong and the audio had
lots of punch" on his end. For me, his signal
was strong, but sounded a bit muddy. I'm still
leaning towards the BFO needing to be tweaked
a bit. With some stations being very strong,
it became more apparent that an AGC would be
beneficial, but that was already planned.

At a glance, it seems like other stations have
an easier time hearing me than I do hearing
them, but this (yesterday!) is just day one.

[COMMENT... I think the tiny speaker I'm using
makes a lot of received signals sound muddy. I
haywired the plug from a headset across the speaker
terminal today and the RX audio was a lot better.]

--
73 Keith VE7GDH


Re: the device is operational!

Keith VE7GDH
 

I checked into the Aurora Net on 7055 KHz again
today (I don't believe our American friends can
operate voice there) and like yesterday, noticed
one station that was very strong and all but
un-readable. I confirmed today that it was a
station just 2 km from my location. I'm guessing
that he overloads the front-end and drives the
audio circuits into distortion unless the volume
is all but all of the way down. It will be
interesting to see how well the audio AGC deals
with it when it is added... or does someone
already have first-hand experience with stations
that strong?

I'll be in and out of the shack this evening,
but listening on 7277 KHz while I'm in... at least
until the AM broadcast station a couple of KHz
below there fades in and I get tired of listening
to the heterodyne. What... no notch filter? hi!
If I think of it, I'll throw a CQ out there at
the top of the hour and every 15 minutes.

--
73 Keith VE7GDH
CN88 Salt Spring Island, BC


Re: W8TEE - VFO /DISPLAY -USB?

Jack Purdum <econjack@...>
 

It looks like that should be fairly easy to do. First, however, I want to get the basics done. Still waiting on Dennis, who is in the middle of moving into a new home.

Jack, W8TEE



From: Joe <joeman2116@...>
To: BITX20@groups.io
Sent: Thursday, July 20, 2017 7:32 PM
Subject: [BITX20] W8TEE - VFO /DISPLAY -USB?

Jack,

I was wondering if you will be adding USB?  
There are many who enjoy the digital modes and would love to be able to use the Bitx40 with your configuration
The  Colour Display sure makes the rig look great.

Thanks for all your contributions to Ham Radio

Joe (Retired but building )
VE1BWV
 



Virus-free. www.avast.com


Re: Bitx40 on 24v

Vince Vielhaber
 

At 24v with a somewhat loud hallllloooo into my service monitor, it reads 18 watts. I imagine I could get louder but 18 is fine by me.

Vince.

On 07/20/2017 02:41 PM, Stephen Harrison wrote:
I have adjusted mine as well and could still get 100 milliamps idling
and just over 1 amp with loud audio no problem. I measure power on my AM
rigs with a dummy load and diode, but using the same technique the
output seems low with SSB. Only about 13 watts. Wondering if it's a
measurement issue or if I have the radio adjusted wrong.



Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------
From: Vince Vielhaber <vev@...>
Date: 7/20/17 14:18 (GMT-05:00)
To: BITX20@groups.io
Subject: Re: [BITX20] Bitx40 on 24v


I did. Mainly 'cuze I figured it would be ilding over 100ma with the
higher voltage.

Vince.



I curious about this also. Â Being that I now have mine setup, if I want
to switch to running a higher voltage on the PA someday, do I need to go
back through the calibration process again. Â To me it seems like you
would because I'm thinking that just applying the higher voltage to the PA
would give you some unspecified current through the PA if it was
originally set to run at 1A. Â With a higher wattage output he PA would
also draw more current and if it's putting out more power it in turn
should also cause more heat that would need dissipated. Â If this is the
case then wouldn't you have to adjust the current through the PA to
something higher than 1A? Â If you do, what's the safe operating area that
you can run a properly heat sinked IRF510 in this radio. Â I thought I
remembered the spec sheet saying something like 4-5.5A based on
temperature.

--
Michigan VHF Corp. http://www.nobucks.net/ http://www.CDupe.com/
http://www.metalworkingfun.com






Re: Bitx40 on 24v

John Smith
 

Ditto on yes or no. I had it adjusted for 12V, switched to 24V and the measurements were just a little bit higher. I adjusted them according to the instructions at 24V, then switched back to 12V and again, not much of a change to bother with. Having done it this way, I am confident either way I power the PA. I checked it again after a couple of months and found a small increase had occurred, and adjusted it then. 200mA max differences were observed. 


W8TEE - VFO /DISPLAY -USB?

Joe
 

Jack,

I was wondering if you will be adding USB?  
There are many who enjoy the digital modes and would love to be able to use the Bitx40 with your configuration
The  Colour Display sure makes the rig look great.

Thanks for all your contributions to Ham Radio

Joe (Retired but building )
VE1BWV
 


Re: Raduino v1.20 (with standalone si5351 routines) released

Dexter N Muir
 

More to that: the IDE shows a 'footer' space below the main 'edit' screen, much akin to the 'Tab' space above. I wonder why that was not used?


Re: the device is operational!

Keith VE7GDH
 

Ryan W7RLF

Another BITX40 owning ham in Spokane and I are going
to do a sched this evening around around 8pm if you'd
like to join in...
I assumed that was 7277 KHz. I was tried calling a few
times (100W) but couldn't hear anyone. Was I on the right
frequency?

I commented yesterday that the receive audio was a bit
muddy/distorted and that perhaps I needed to tweak the
BFO. I just bridged the tiny speaker that I am using
with some earphones. The audio was infinitely better
on them. I'll have to get a better speaker connected
and find a jack for the earphone that isn't too "short"
to mount on front of the case. Both will be huge
improvements for me.

The clicking heard when tuning is gone... at least I
can't hear it on the tiny (28mm) speaker. Raduino v1.2
must have taken care of it. I don't have any by-pass
caps across the Raduino voltage regulator yet.

I checked onto the noon-time net on 7383.5 KHz again.

--
73 Keith VE7GDH


Re: Raduino v1.20 (with standalone si5351 routines) released

Dexter N Muir
 

Thanks Thomas. D'oh - noob me. Play with the menus ... :) I've been 'spoiled' by pfe (Programmers File Editor, an 'oldie') - that has by default line and char-pos (at cursor) numbers in a 'footer'. Less wasted screen width and 'clutter'. It also has a Macro facility, recording keystrokes for repetitive ops. A widoze app (run under wine), and haven't found a Linux equivalent.


Re: the device is operational!

Keith VE7GDH
 

Mike WA1MAD wrote...

Do I see room to the left for a battery? I use an
internal battery to be truly portable.
I casually thought about it. The bolts that hold the
feet on and hold the top of the case will reduce the
room by a bit, but it might be doable.

--
73 Keith VE7GDH


Re: W8TEE Assembly Manual and Code Update

Art Olson
 

Jack

 

Loaded the updated sketch. No VFO output from Out or Out2. Reload previous sketch and restored normal operation

 

art

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Jack Purdum via Groups.Io
Sent: Thursday, July 20, 2017 11:27 AM
To: BITX20@groups.io
Subject: [BITX20] W8TEE Assembly Manual and Code Update

 

All:

I have added code and instructions for activating the voltage monitor field and also the implementation of Fast Tune. The manual is in the File section under W8TEE-B40AssemblyManual03.doc. You also need the updated source code files, which I am attaching here. (I'm not ready to use Github yet.)

Let me know if you find bugs.

Jack, W8TEE




AVG logo

This email has been checked for viruses by AVG antivirus software.
www.avg.com



Re: Starting Over

John Backo
 

Curt:

No, it is not extraordinary. These power MOSFETS are
extremely variable. It is unlikely that anyone's results can be
exactly duplicated. The only real solution is to change the
device, and hope you have better luck with the new one.

The best approach is to be happy with what you have; you
can easily increase the power by going to a 18-24v drain, being
very careful to re-adjust it right. And increasing the heat-sink
considerably.

john
AD5YE


Re: Bitx40 on 24v

John Backo
 

Steve:

The answer to your question is "yes and no, probably yes".
You are probably better off letting RV1 alone and concentrating on
R136, the transistor drive.

The reason being that RV1 is a very close and somewhat touchy adjustment.
I have noted elsewhere that you should start the adjustment of RV1 with the
PA drain disconnected. Adjust the gate voltage to about 2-2.5v. Then connect the
drain to 24v with an ammeter and VERY SLOWLY adjust RV1 until you see an additional
100-120 ma, current draw. That will give a gate voltage of around 3v. That is about as
close to the linear region of these power MOSFETS as one can get.

Then connect your ammeter again to the drain and adjust R136 for about 1-1.2A total draw
at 24v. That should give you about the best output. Everyone will get a different result
because these devices are extremely variable. Another major consideration is to increase
the heat sink area considerably -- 8x greater area is probably not excessive.

A proper outcome is about a 4-fold increase is power output. Don't forget to *always* load your
antenna with about 50 ohms impedance. This is very important.

Sometimes you will get VHF oscillation at higher voltages (or at 12v, for that matter). Usually this
can be cured by adding a few hundred pF capacitor at the drain or across the windings of the
output transformer. YRMV.

john
AD5YE


BITX QSO Night, Sunday, July 23, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere

KC8WBK
 

BITX QSO Night, Sunday, July 23, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere

Join us as we make contacts from BITX40 to BITX40 on 7.277 MHz in 40 meters!

To participate, call CQ BITX at 7pm sharp, your local time, on Sunday. Call off and on for about 15 minutes. It is helpful if you call CQ BITX with your name and location.  Repeat your call a number of times if conditions are weak.

This is a worldwide event at 7pm in each time zone.  You may participate in any time zone, regardless of your location, so you may wish to call in at 6pm, 7pm and 8pm, your local time, to contact hams in adjacent time zones.

The backup frequency in case of QSB or other noise is 7210 kHz.

Report your QSO's, discuss propagation, noise, signal reports, audio reports, antenna type, etc. in this thread.

This is an undirected, scheduled event.  The BITX QSO Night relies on you to call CQ BITX to initiate contacts with other stations, so warm up that final and transmit a few calls at 7pm on Sunday.  Talk to you then!