Re: First real try at 80 meters using QRPKITS 80M low pass filter
Would you be able to scribble down a portion of the schematic, putting the original capacitors etc in black, and your changes? for 60 meters?in RED or some other color, and then take a photo with a cell phone camera and post it here for posterity?? ?That
might help out other people......
Gordon?
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I need to correct one thing it should be 100pf on L7 not 470pf sorry chris
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Re: First real try at 80 meters using QRPKITS 80M low pass filter
I need to correct one thing it should be 100pf on L7 not 470pf sorry chris
On 28 Nov 2017 13:33, "Gordon Gibby" < ggibby@...> wrote:
?thank you for that infomration!!!!
Nice for 60m add the 470 to L7. And add 150pf to each cap C2,C4,C6 to the bpf I get 8watt with 12,2v and 10watt with 12,8v chris
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Re: First real try at 80 meters using QRPKITS 80M low pass filter
?thank you for that infomration!!!!
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Nice for 60m add the 470 to L7. And add 150pf to each cap C2,C4,C6 to the bpf I get 8watt with 12,2v and 10watt with 12,8v chris
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Re: First real try at 80 meters using QRPKITS 80M low pass filter
Nice for 60m add the 470 to L7. And add 150pf to each cap C2,C4,C6 to the bpf I get 8watt with 12,2v and 10watt with 12,8v chris
On 28 Nov 2017 13:26, "Gordon Gibby" < ggibby@...> wrote:
?very cool.? ?I'm using the cheap solution of a 470 pf strapped from one end of the BPF to the other so I don't know exactly where it is optimized....perhaps I can get some rough measuresments of that by looking at received signal....
I found my bitx on 80m gave 5watt on 3,799 and on 3,500 gave 6watt I got a lpf /bpf? coming from QRP labs the ones I was using where copy's and not working well but my bitx on 60m I get the same power as my 40m one and it works well?
Chris?
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Hello all, As said in datasheet of SiLabs, decoupling and ground plane is very important (see ¡ì6) On raduino the GND via is too far from chip !! ..and it causes a common impedance to ALL outputs ! May be with arranged layout and better GND we can improve spurs... I did several tests and trails to improve bridies and spurious of the Raduino module : /g/BITX20/message/33741- with one activated output : it is clean ! - loading all 3 outputs at 50 ohms instead of one makes more bridies ! - grounding the Xtal casing : no improvement - having seperate 50 ohms coax is better, but there is still coupling on tracks from the chip to Raduino's terminals (puting the finger on it increase more spurs) - reducing the driver output current and power improve much more better : at level 1 (4 mA) I have +8.5 dBm, with a 2 dB attenuator pad it is just sufficient for +7dBm mixer with 0.1 dB added loss compared to +10 dBm drive at level 2 or 3 - I will try at level 0 (2mA) +4.5dB without attenuator to mixer... - using industrial mixers with -50 to -60dB LO rejection are better than self made mixers : TFM-2, SBL-1, SRA-1 ... the coupling LO to RF or LO to IF is reduced I aggree with Henning notes and will try to change 2nd osc to 33 MHz (but 33-11.997... = 21.003.. MHz !),or find a 33 Mhz xtal... For Dimitar, I tried activating PLL B on Farhan's software : no change on spurs ! I found on library that PLL B is not affected on CLK0,1,2? anyway ! Now I'm using Allard's subroutines to configure the Si5351 instead of the library, I spare about 10 ko of ROM in the Nano !!! but no change on bridies? ! I'm rebuilding the Ubitx software from Fahran with corrections, improvements and? Allard's tricks : real dual VFO, A=B, RIT, new Smeter, adding voltmeter, tuning more stable,... Now I'm facing to CW mode and review the compete function... I'm not an expert in C++ , I started to learn since september with this project (I have a stong backgrouned in assembler) ?To EB7ME, is your receiver clean ? Did you try with antenna connected to a dummy load ? 73 de F5RCT Jean-Matthieu
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Re: First real try at 80 meters using QRPKITS 80M low pass filter
?very cool.? ?I'm using the cheap solution of a 470 pf strapped from one end of the BPF to the other so I don't know exactly where it is optimized....perhaps I can get some rough measuresments of that by looking at received signal....
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I found my bitx on 80m gave 5watt on 3,799 and on 3,500 gave 6watt I got a lpf /bpf? coming from QRP labs the ones I was using where copy's and not working well but my bitx on 60m I get the same power as my 40m one and it works well?
Chris?
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Re: First real try at 80 meters using QRPKITS 80M low pass filter
I found my bitx on 80m gave 5watt on 3,799 and on 3,500 gave 6watt I got a lpf /bpf? coming from QRP labs the ones I was using where copy's and not working well but my bitx on 60m I get the same power as my 40m one and it works well? Chris?
On 28 Nov 2017 12:36, "Gordon Gibby" < ggibby@...> wrote:
?I'm sorta simple and goal directed --- In the prototype version for the ARES group I'll add another toggle switch to switch an 80 meter LPF in and out somehow.? ?I? *thought* I had seen higher output on an earlier much simpler trial --- but was rushed and
just got the basics going, will fiddle more with it later.
Used it later in the evening to make WINLINK connections to 3 different RMS servers in different states.? ?
In the middle of the night, the Critical Frequency lifts a bit in the southern US and it went above the 80 meter band & I was able to get a strong signal from a WINLINK RMS just 65 miles from me --- way too far for ground wave, but even with just 5 W output
was able to transact email with that RMS (tho it took a lot of repeats)
It is so neat to be able to shift this rig to different bands!!!!!? ?Been doing ham radio for about 45 years, this is the first time I've really gotten into the guts of drastically modifying any rig.? ?This is just like a solid state version of a Heathkit
SB-102 transceiver.? ??
Gordon?
Very nice! A simple way to go to 80m, certainly simpler than my multi-band conversion.?
--
Ryan Flowers W7RLF
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Re: First real try at 80 meters using QRPKITS 80M low pass filter
?I'm sorta simple and goal directed --- In the prototype version for the ARES group I'll add another toggle switch to switch an 80 meter LPF in and out somehow.? ?I? *thought* I had seen higher output on an earlier much simpler trial --- but was rushed and
just got the basics going, will fiddle more with it later.
Used it later in the evening to make WINLINK connections to 3 different RMS servers in different states.? ?
In the middle of the night, the Critical Frequency lifts a bit in the southern US and it went above the 80 meter band & I was able to get a strong signal from a WINLINK RMS just 65 miles from me --- way too far for ground wave, but even with just 5 W output
was able to transact email with that RMS (tho it took a lot of repeats)
It is so neat to be able to shift this rig to different bands!!!!!? ?Been doing ham radio for about 45 years, this is the first time I've really gotten into the guts of drastically modifying any rig.? ?This is just like a solid state version of a Heathkit
SB-102 transceiver.? ??
Gordon?
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Very nice! A simple way to go to 80m, certainly simpler than my multi-band conversion.?
--
Ryan Flowers W7RLF
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think about the fact, that three squarewaves are generated within
a tiny chip, for clocking digital circuits crosstalk normally is
not a bit issue, but for analog circuits this must be an issue!
This means that to use three SI5351 for individualt frequecies
seems to me the best solution. The chips are cheap!!
For best freqeuncy stability only one xtal osc ( TXCO or even
OCXO 25 MHz or 27 MHz) should be used, but its three outputs must
be "perfectly decoupled" meaning mimimize the crosstalk between
the outputs of the buffer stages.
Another thought:
The second osc for the conversion 45 MHz - 12 MHz should not be
blaced within the range of the first LO i.e. 45 + 12 = 57 MHz) but
45 - 12 MHz = 33 MHz. This is quite close to the maximum input
frequency of the uBITX (30 MHz).? Lowering the second IF to say 5
MHz would ease the situation.
At least: the phase nosie performance of the SI5351 is not at its
best and degrades the higher the output frequency is.
Henning Weddig
DK5LV
Am 28.11.2017 um 05:09 schrieb VK3HN:
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Hi Roberto and
Andrew
I have a part built ubitx as well.? I ran Raduino software on
Arduino nano, using all 3 clocks, and found the large number and
strength of birdies on all bands made the rx unusable.? I assumed
the si5351 was just too dirty when using 3 clocks.? However I
moved onto another project and did not spend time debugging my
build.? Did you use si5351 and if so, is it clean enough?
73 Paul VK3HN.?
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Re: First real try at 80 meters using QRPKITS 80M low pass filter
Very nice! A simple way to go to 80m, certainly simpler than my multi-band conversion.?
--
Ryan Flowers W7RLF
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Hi All,
From my experience with si5351 , I think results will be bether when use crystal BFO with another one 12 MHz crystal, like other projects from Mr. Farhan, and use A and B channel from Si5351 to drive other - VFO and SECOND_OSCILLATOR. (I know that Si5351 has 2 channels - A and B, and 3 outputs CLK0,1,2 - 2 outputs share 1 channel (I think this is B channel)). This is easy to read from documentation. If we found 57 MHz crystal will be better to make second oscillator with crystal to.
(I'm also have soldered but freezed uBitx old schematic experiments :) )
73! Dimitar
On Tuesday, November 28, 2017, 9:14:51 AM GMT+2, Ashhar Farhan <farhanbox@...> wrote:
The birdies are a result of the oscillator radiating out from the wires. If there are ground loops or wires connecting the radiuno to the main circuit, you will get these birdies for sure.? just for this, the raduino has a number of ground lines on both sides of the oscillator outputs. see the pictures of ubitx builds to see how i have soldered the raduino connector directly to the ground plane. with this, all the birdies are virtually gone.
- farhan
On Tue, Nov 28, 2017 at 9:39 AM, VK3HN <prt459@...> wrote: Hi Roberto and Andrew
I have a part built ubitx as well.? I ran Raduino software on Arduino nano, using all 3 clocks, and found the large number and strength of birdies on all bands made the rx unusable.? I assumed the si5351 was just too dirty when using 3 clocks.? However I moved onto another project and did not spend time debugging my build.? Did you use si5351 and if so, is it clean enough?
73 Paul VK3HN.?
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The birdies are a result of the oscillator radiating out from the wires. If there are ground loops or wires connecting the radiuno to the main circuit, you will get these birdies for sure.? just for this, the raduino has a number of ground lines on both sides of the oscillator outputs. see the pictures of ubitx builds to see how i have soldered the raduino connector directly to the ground plane. with this, all the birdies are virtually gone.
- farhan
On Tue, Nov 28, 2017 at 9:39 AM, VK3HN <prt459@...> wrote: Hi Roberto and Andrew
I have a part built ubitx as well.? I ran Raduino software on Arduino nano, using all 3 clocks, and found the large number and strength of birdies on all bands made the rx unusable.? I assumed the si5351 was just too dirty when using 3 clocks.? However I moved onto another project and did not spend time debugging my build.? Did you use si5351 and if so, is it clean enough?
73 Paul VK3HN.?
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After changing the IRF, did you set the 100mA current with the bias preset pot (blue) ?
Set the blue preset fully clockwise and see what current you get. When you press PTT the current will not change much. Slowly
advance the preset anticlockwise till the final draws 100Ma or increases total current by 100mA.
High current also happens if the gate is open.
Raj
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At 27-11-2017, you wrote: Hi, Was busy with my Bitx40, and i saw "smoke". I replaced the Power amp. The receiver works, and if I press the ptt it clicks, and the ammeter rises to about 3.2A, but no audio output.
Any help would be appreciated.
73
Evan
ZS6ELI
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Re: BITX QSO Night, Sunday, November 26, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere
Willy,
Just a follow-up, I stayed up all night and nothing opened up. Kept
looking for you
but just a s9 noise level.
Ed W0OIC
On 11/26/2017 2:20 PM, Willy wrote:
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I have been looking at?
and the results are very much what I have been experiencing on
QSO night.
It is also a very good predictor of what other times might
produce.
I entered my grid square FN41hm, power 10 watts SSB, dipole
at 15 meters,and the receiving station antenna as dipole at 15
m also and moved the
receiving station around with my mouse to see the likely
percentage of a successful contact at any time.
At 00z? (my 7 PM) I have less than a 50% chance of working
Tom VE3THR at FN04ej around 500 miles and the chances drop to
18% an hour later.My best? ? ? ? ? ? ?chance to work Tom is
between 1 PM and 5 PM local when I have over a 90% chance.
At 00z my chance of working W0OIC ED EN42qm at around 1000
miles is 74% and stays above 60% til my 3AM when I have my
best chance 75% if Ed is still up.
Of course VOACAP is only a guide but a huge amount of time
and money was spent building these models?
?
Hope to work you tonight, Willy
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Hi Roberto and Andrew
I have a part built ubitx as well.? I ran Raduino software on Arduino nano, using all 3 clocks, and found the large number and strength of birdies on all bands made the rx unusable.? I assumed the si5351 was just too dirty when using 3 clocks.? However I moved onto another project and did not spend time debugging my build.? Did you use si5351 and if so, is it clean enough?
73 Paul VK3HN.?
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Perhaps you are measuring harmonics, If i am right. ?try a small LPF and then check.? Reduce the gain of the counter 's pre-amplifier.
On Tuesday, 28 November 2017 9:29 AM, "robert.m.cox@..." <robert.m.cox@...> wrote:
I have built the W8TEE B40 and the display works along with the rotary encoder but the AD9850 is not working properly in the code.?
The output frequency of the 9850 at 7.000.000 Mhz is 39.2 Mhz and at 7.300.000 MHz it is 54.2 Mhz. Clearly nowhere close to 5Mhz or 4.7Mhz.
I have written a small sketch using the?AD9850SPI library and I can set the output frequency to 5Mhz just fine like this:
void sendFrequency(int32_t frequency) {
? DDS.setfreq( (float) (5000000), 0);? ?// Second argument is phase. See library docs
? myDelay(10UL);
}
However when I do the same thing in the B40 code (that is manually set the frequency to 5MHz like in my example sketch) the frequency that I read on my frequency counter is 39 - 54 Mhz.
Has anyone else seen this? What am I doing wrong?
Thanks in advance.
73,
-Rob (N4MN)
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I have built the W8TEE B40 and the display works along with the rotary encoder but the AD9850 is not working properly in the code.?
The output frequency of the 9850 at 7.000.000 Mhz is 39.2 Mhz and at 7.300.000 MHz it is 54.2 Mhz. Clearly nowhere close to 5Mhz or 4.7Mhz.
I have written a small sketch using the?AD9850SPI library and I can set the output frequency to 5Mhz just fine like this:
void sendFrequency(int32_t frequency) {
? DDS.setfreq( (float) (5000000), 0);? ?// Second argument is phase. See library docs
? myDelay(10UL);
}
However when I do the same thing in the B40 code (that is manually set the frequency to 5MHz like in my example sketch) the frequency that I read on my frequency counter is 39 - 54 Mhz.
Has anyone else seen this? What am I doing wrong?
Thanks in advance.
73,
-Rob (N4MN)
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First real try at 80 meters using QRPKITS 80M low pass filter
Tonight soldered together the beefy qrpkits 80 meter low pass filter and hung it on the output of my modified bitx40 (with 470 pf capacitor across the bandpass filter).? Bitx40?BNC to BNC filter input;? filter output?BNC to PL259 to cheap radio shack SWR/"wattmeter"?
into heathkit ancient tuner set to a good SWR around 1.4 with an antenna analyzer.? ?3740 khz roughly (avoided QSO's of course).? ?The receiver is plenty sensitive, the atmospheric noise and crashes are quite distinct.? ?I now have a little toggle switch to
connect/disconnect the 470pf mica capacitor moving the bandpass filter around.??
My whistles are pretty pathetic but showed 5W output with a 12 volt gell cell powering the unit that hasn't been charged in a while.? ?Same on upper and lower.? ?I did only?one test without the filter and the output was similar, so the insertion "loss" isn't
significant.? ?
When I have more time I'll put a 50 ohm dummy cantenna on it and get a signalink and test more carefully with tones from FLDIGI.? ?I also have a 19V supply for the PA and can test that.? ?
But it definitely?seems to work.? ?Using an old SB-102 Heathkit with only a few inches of "antenna" I? was able to listen to myself in headphones and voice?sounded fine.? ?
The goal is an inexpensive training rig for the local ARES group members who have never had an HF rig, to both allow them to gain some more building experience, and then to be able to do local voice net and some WINLINK on 80/40 meters as well.? ? I've already
used the rig to make WINMOR contacts to multiple 40 meter WINLINK gateway?stations.? ?
I altered Allard's code to cause the end-of-10K potentiometer moves to go quickly when not within a ham band, and to slow down to plodding when INSIDE a ham band (actually slower than he had it to give my ancient reflexes time to react)??
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Re: Allard's Modifications
Thanks, Marco!
Jack, W8TEE
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Re: Multiband BITX40 with pluggable filter modules
I plan to build something similar using a separate BPF and LPF each for 160m, 80m, 40m, 30m, and 20m. ?Call it FrankenBitX, BruteForceBitX, or maybe DontKnowWhatImDoingBitX.
It would work without individual filter sets for each band, but I do not really understand filters yet and have not yet built Ashhar's Specan.
Ashhar's uBitX is an elegant design, and I have gathered the parts to build a uBitX, but construction will take weeks or months (for me, anyway).
A multiband-converted BitX similar to yours could be assembled in a few hours, and that's just sooooo tempting.
Care to offer any suggestions, advice, or (constructive) criticism?
73 de w9ctw
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Jean-Matthieu F5RCT
Raj vu2zap
VK3HN
Rob Cox (N4MN)
Craig Wadsworth