Re: Was Noob in need of some assistance. Now: [BITX20] Input antenna attenuation?
Yes I have used batteries to power it. 4 18650's 4.1v li-ion batteries. Then a nice 7812 regulator. Tried that 3 weeks ago.?
I didn't build an attenuator so I didn't force feed it a signal like I had planned. I ended up at work all weekend :-(?
The psu I am using is a korad linear power supply. 20 micro volt peek to peek.
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Re: adding VK3YE AGC to BITX40
Nice write up Paul. I am very happy with the VK3YE AGC. It provides just the right amount of AGC action for my tastes and after many hours of operating with it in all kinds of band conditions I have not heard it do anything annoying. I put a switch in series with the LDR so I can turn the AGC off but it is always on. I built my rig from scratch in a modular fashion and that audio board with Peter's AGC will surely get reproduced and used in my future projects. Your white LED probably works as well or even better than the red one I used. The LED and LDR I used are: http://www.taydaelectronics.com/led-5mm-red-water-clear-ultra-bright.html
73 - Jerry W0PWE
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Re: Simple audio muting circuit
NM I just read it a 3rd time you said the coil not the tx/rx switching. So just between the coil power cathode to +
On Mon, May 1, 2017 at 7:02 AM, Steve Greer <km4ous@...> wrote: Are you referring to the 2 diodes for strong signal rejection?? So you added to same pins as K2?
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Re: Simple audio muting circuit
Are you referring to the 2 diodes for strong signal rejection?? So you added to same pins as K2?
On Mon, May 1, 2017 at 1:07 AM, John Pieper <j.pieper@...> wrote: Something else I should mention: I have been puzzled by the circuit around the K1 coil, and suspect that it might not optimally protect any semiconductors connected to the PTT line. So before doing this mod, I installed another diode across the K1 coil in the conventional manner (see K2). Just a little cheap insurance. John AD0RW
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Re: R15 and ADE-1 mixer getting very hot
Hi Mike, also for me was not posible to find the schematic using ADE-1. I got the one with SBL-1 and redrawn the mixer part with the ADE-1 as positione on back of pcb. Herewith is the drawing.
73 Gian I7SWX
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Re: raduino_v1.08 released
Allard, Just wish to add my thanks for the great job you have done with the sketch. Compiles, uploads and works a treat. 73 Howard, VK4BS
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Re: European Bitx Net - Tonight (1 May) 1900UTC 7175 kHz
my Bitx40 is order but not arrived so have to wait until next time
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European Bitx Net - Tonight (1 May) 1900UTC 7175 kHz
EUROPEAN BITX NET - TONIGHT (1 MAY) 1900UTC 7175 KHZ? I would like to suggest we try to start a European Bitx?Net each Monday night starting 1900UTC.
I suggest we congregate on 7175 kHz for check-ins and signal reports (if 7175 is in use please move upwards in frequency until you find us). It would be great if we could encourage some Bitx to Bitx?QSOs although of course everyone is welcome to join the net irrespective of transceiver or location. Anyone interested in joining us?? de Carl, M0ICR
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Re: R15 and ADE-1 mixer getting very hot
Hi William,
no more news from you. Did you find the problem? From your reporting of Q7 disconnection and still have problem with R15 heating up there could be a short to gnd at pin 6. This would heat up the ADE LO transformer also. The other case where the mixer and R15 would get hot is if the RF or IF pins would be shorted to gnd as this would be reported as a short to LO, but removing Q7 the only point is a short at pin 6 as if at pin1 only R15 would heat up.
73 Gian I7SWX
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Re: raduino_v1.09 with RIT (SPLIT) functionality
Sorry, there was an extra dot "." at the end of the URL.
Please try again without the dot:
73, Allard PE1NWL
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On Mon, May 1, 2017 10:28, bengt-ingvar.andersson@... wrote: Thanks again Allard for fine program !
I could not find the sketch on the address ? (Error 404)
Ingvar
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Re: raduino_v1.09 with RIT (SPLIT) functionality
Without the dot after the address it worked.
All ok so far.
Ingvar
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Re: Simple audio muting circuit
John Wondering if the added diode alone did anything? ?Did you try this by itself?
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Re: raduino_v1.09 with RIT (SPLIT) functionality
Thanks again Allard for fine program !
I could not find the sketch on the address ? (Error 404)
Ingvar
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Re: Was Noob in need of some assistance. Now: [BITX20] Input antenna attenuation?
Hi,
I was looking at your first post on this subject and I noticed you described your PSU as 'semi clean'. How clean is it ?
You understand that the Bitx Rx architecture has been described by it's creator (Farhan) as not unlike a DC receiver in that it has only very moderate gain at RF and IF and that this lack of RF/IF gain is made-up for by high gain in the audio stages, especially the audio preamp stage. This of course will make the Bitx sensitive to noisy DC power (like a DC receiver).
I am thinking what could be making all the noise (static as you call it) you are hearing from your Bitx.
Have you tried running your Bitx off a battery supply, you can not get much quieter than a battery.
A couple of cheap 6v lantern batteries (the ones with the spring terminals) in series should do the job.
Regards,
Peter VK1XP
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On 01-05-2017 10:58, stronggeek30s@... wrote: So when I turn on my sig gen the static shoots through the roof
regardless of the frequency the sig gen is set to. I initially thought
something was wrong with it so I scoped the output and it seems like a
nice and clean output.
When I tune the sig gen to 7.1mhz (+/- 1mhz) and the radio is tuned to
7.1mhz the static quadruples in volume. That is regardless of the
position of the xmit antenna (6 inch wire hanging off the sig gen).
I also received an rtl/sdr usb dongle. plugged it into my 40m antenna
and I can find and listen to all kinds of signals. Though it seems
like all I find are just solid tones and maybe a few ppl transmitting
morse code(assumption) .
Links:
------
[1] /g/BITX20/message/25873
[2] /mt/4971398?uid=236039
[3] /g/BITX20/post
[4] /g/BITX20/editsub?uid=236039
[5] /g/BITX20
[6] /static/tos
[7] /g/BITX20/leave/defanged
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Re: Simple audio muting circuit
Something else I should mention: I have been puzzled by the circuit around the K1 coil, and suspect that it might not optimally protect any semiconductors connected to the PTT line. So before doing this mod, I installed another diode across the K1 coil in the conventional manner (see K2). Just a little cheap insurance. John AD0RW
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A week ago doing a qso I felt the final was getting hot.? I used a 8v battery with a repaired 2x2" fan blowing on the heat sink.? At 8 volts fan was low in noise.? I think that helped with the final heat.? Because I can't tell what my SWR is I set my match box to the 40 mtr setting I use with my Marauder HX10.? I need to get the CW hack put in so I can load the BITX40.? My BITX40 is getting powered from ?8AH 12v. battery. Tonight the QSO party got busy about 2100 CST.? I think the time zone made the QSO party late...but the band was better.? There was a wide band buzz signal that I also heard on SDR located out of MI.? Seems it was everywhere.? Good night however considering the QSB and QRN.? My 40 mtr dipole is 10' high and oriented E/W.? With that I QSO with W1ly and my friend in HOVLAND, MN. ?happy with results that I can make better with higher antenna and the BITX40 in a decent case/box.? I also found when I move the DDS (carefully) to 90 deg to the recvr I can minimize the birdie at 7.199.? So shielding all lines like the DDS and making a separate copper shielded box to separate the DDS from the main PCB maybe very helpful. 73 Larry WA9DOH
On Sun, Apr 30, 2017 at 10:27 PM, ekelley <ekelley828@...> wrote:
OK, My first Bitx40 was 6' away to the workbench next to me. Then I
finished tuning up and worked 2 miles away.
Tonight was better 135 miles away in WI, I believe it was Jay. Then
my final went out - only getting out about 4 watts.
I think the smoke was the clue somethings not right. Well back to
the scope.
Ed W0OIC? - Stay with 7195 lower is bad, higher is bad. 8pm central
time!
On 4/30/2017 9:44 PM, Willy wrote:
Got started late (9:55EST) 01:55z
?but worked several BitX40 from Rhode Island
7.195 KHz
Pwr=7w into an inverted V @ 20 meters
KD9CKB Jay in WI
WA9DOH Larry in IL
KM4YEC Craig in TN
Also worked ME,PA,and Puerto Rico
Lots of QSB, off the air at 02:30z
Willy W1LY Jamestown, RI
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Re: raduino_v1.09 with RIT (SPLIT) functionality
Thank you for all your work on this. ?I plan on implementing your sketch soon and am excited about all the features you have added to the BitX40. ? If I could make a request - can you add an S-meter to the sketch.? Thanks Tim
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OK, My first Bitx40 was 6' away to the workbench next to me. Then I
finished tuning up and worked 2 miles away.
Tonight was better 135 miles away in WI, I believe it was Jay. Then
my final went out - only getting out about 4 watts.
I think the smoke was the clue somethings not right. Well back to
the scope.
Ed W0OIC? - Stay with 7195 lower is bad, higher is bad. 8pm central
time!
On 4/30/2017 9:44 PM, Willy wrote:
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Show quoted text
Got started late (9:55EST) 01:55z
?but worked several BitX40 from Rhode Island
7.195 KHz
Pwr=7w into an inverted V @ 20 meters
KD9CKB Jay in WI
WA9DOH Larry in IL
KM4YEC Craig in TN
Also worked ME,PA,and Puerto Rico
Lots of QSB, off the air at 02:30z
Willy W1LY Jamestown, RI
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Mike:
On 40m this time of the year, the atmospheric noise is very strong.
With this simple a receiver, you might hear something at a 1uV level,
but it would be pretty much buried in the noise.
10uV is a very strong signal. If it were a SSB signal, it would probably be booming in.
I have not measured the MDS of the BITX, but I imagine it is realistically in the region
of 3uV.
On 17m, you probably would weakly discern the 1uV signal. It may be S2, but likely Q5.
The birdie is internally generated and is always there.
john
AD5YE
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Re: Simple audio muting circuit
I think you are confusing the 2N3906 (PNP) and the 2N3904 (NPN).
It is easy to do. They are complementary.
john
AD5YE
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Giancarlo - I7SWX
Allard PE1NWL
ekelley