I'm new to this. I just got my Bitx40 in and built in a box. I'm trying to upgrade the nano but I cant get past selecting a port. I'm using Arduino IDE for windows. When I go to port it is not hi-lighted. Any ideals. ?
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Topology of Bitx40 bandpass filter
Does anyone know what it is? ?It has remarkable characteristics. ?I've extrapolated it to make equally performing filters for all the other bands (confirmed with Elsie) but would like to know what I'm making...
..thanks
Burton Ison W5IAC
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And this is why I love this hobby and this list. Thanks Mike!
regards, Richard?
On Apr 2, 2017 2:58 PM, "Michael Hagen" < motdog@...> wrote:
You might put a 1K in series with the input.? Thus it would take
a larger signal but load the test circuit less.
Try on the gate of the IRF510?? That's a pretty good stiff signal
at your transmit frequency.
Try it on the SL5351 output.
It is good to experiment, this radio has a lots to learn about!
It is a wonderful base to experiment with.? I will use mine
mostly for playing with the receiver and Arduino code.
I don't have an antenna.? So it will be a long wire out the door
and /or the Signal Generator!
I have already made PCBs (stamp sized) for the Silicons Labs
oscillator and have a Nano driving it with I2C.
The examples in the Arduino Code work!? Sweeping, Fixed Freq.
ect.? The library makes it magic.
Mike, WA6ISP
On 4/2/2017 11:27 AM, richard kappler
wrote:
Nothing in particular, trying to learn.
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Re: State of the EEPROM After a Download
From other projects I have made with custom EEPROM settings, I have found the EEPROM is unchanged untill there is a write or put performed.
--
73 de Noel, ZL1NC
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You might put a 1K in series with the input.? Thus it would take
a larger signal but load the test circuit less.
Try on the gate of the IRF510?? That's a pretty good stiff signal
at your transmit frequency.
Try it on the SL5351 output.
It is good to experiment, this radio has a lots to learn about!
It is a wonderful base to experiment with.? I will use mine
mostly for playing with the receiver and Arduino code.
I don't have an antenna.? So it will be a long wire out the door
and /or the Signal Generator!
I have already made PCBs (stamp sized) for the Silicons Labs
oscillator and have a Nano driving it with I2C.
The examples in the Arduino Code work!? Sweeping, Fixed Freq.
ect.? The library makes it magic.
Mike, WA6ISP
On 4/2/2017 11:27 AM, richard kappler
wrote:
toggle quoted message
Show quoted text
Nothing in particular, trying to learn.
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The sketch by Gene Marcus W3PM can be found in the group and does what you want. ? v/r Fred W4JLE ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of Mike via Groups.Io
Sent: Sunday, April 2, 2017 7:53 AM
To: [email protected]
Subject: Re: [BITX20] Raduino BFO hook up? ? Does anyone know of Arduino code that works on a Arduino with an encoder that handles 10 MHZ and below (LSB) and above USB with the correct frequency readout? The Pa3fat code I am using works well below 10 MHZ but 20 meters I am at 9MHZ and tuning is backwards (when display shows going up in frequency.. Output is actually going down) which makes converting tuff!
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Nothing in particular, trying to learn.
On Apr 2, 2017 2:25 PM, "Michael Hagen" < motdog@...> wrote: What do you want to measure?
It has 100 Ohm input resistance on input transistor base ( Cap Coupled).? So you need to find a signal somewhere that this low impedance won't load down?
Mike, WA6ISP
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What do you want to measure?
It has 100 Ohm input resistance on input transistor base ( Cap Coupled).? So you need to find a signal somewhere that this low impedance won't load down?
Mike, WA6ISP
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Richard W2KAP
It is normal to connect your frequency counter to the VFO output, and to program
in an IF offset.? This lets the counter tell you the operating frequency when receiving
and transmitting.? Connecting the counter to the antenna port could be bad for several
reasons.? (1) it would only show frequency when transmitting. and (2) the RF power
available at the antenna port when transmitting could do bad things to your frequency
counter.
Arv? K7HKL
_._
On Sun, Apr 2, 2017 at 12:11 PM, richard kappler <richkappler@...> wrote: I am working on strengthening my kit building skills before I tackle my next Bitx40, so I have built the ?frequency counter and should have the parts for a coupla antenna analyzers tomorrow.
Regarding the freq counter, it has 4 "inputs", a pair of grounds, 8-15 VDC and sig in. I have two questions: 1. Any reason I shouldn't hook the VDC in to the incoming power for the BitX??
2. Regarding Sig In, I should connect this to the brown (center) of the antenna output?
regards, Richard
-- W2KAP In any given circuit, the most expensive part will always sacrifice itself to protect the fuse.
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I am working on strengthening my kit building skills before I tackle my next Bitx40, so I have built the ?frequency counter and should have the parts for a coupla antenna analyzers tomorrow.
Regarding the freq counter, it has 4 "inputs", a pair of grounds, 8-15 VDC and sig in. I have two questions: 1. Any reason I shouldn't hook the VDC in to the incoming power for the BitX??
2. Regarding Sig In, I should connect this to the brown (center) of the antenna output?
regards, Richard
-- W2KAP In any given circuit, the most expensive part will always sacrifice itself to protect the fuse.
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Re: 25 volts and output wattage
If interested in pushing the IRF510, read what kb1gmx has to say in this old thread: ?/g/BITX20/topic/4104262#14524 Better yet, all kb1gmx posts to this forum. ?Plus EMRFD. Alternately, I suggest you buy IRF510's in hundred lot quantities. ?And some safety goggles.
On Sat, Apr 1, 2017 at 12:38 pm, Jerry Gaffke wrote: Could in theory we go higher than 25 watts or would that blow a circuit? Say 36 watts with enough cooling to get maybe 40w or more out? ?
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Re: No audio driver, now RF Probes
Those eBay ones are nifty, I want one.? But, they are 50 Ohms, so not so good at poking around circuits that may be several K Ohms? Mike, WA6ISP
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Dennis and I are finishing up work on an AGC board, from which we grab the S meter data. By having the takeoff for the AGC in the RF chain, Dennis has a pretty good S meter (i.e., not a VU meter). I've also added a little more detail to the S meter graphic to make it look more like an S meter. I'll let the group know where we're done hacking away!
Jack, W8TEE
From: Jerry Gaffke via Groups.Io <jgaffke@...>
To: [email protected]
Sent: Sunday, April 2, 2017 11:52 AM
Subject: Re: [BITX20] No audio driver
If you must have a log amp, I'd make pads for an optional AD8310 (the improved and cheaper AD8307) ?on the main board and have it drive a Nano analog input. ?Make a dandy S meter when not being used to troubleshoot the Bitx or perhaps other gear. ?Those that want it could go out and buy one, or you could make the extra part a buying option at hfsigs. Of course, we'll quickly run out of Nano pins. ?I still like the idea of the Si5351 on the main board, a connector off to the microcrontroller/display of our choice. ?I'd go Teensy 3.2, likely never run out of pins or anything else (mips, flash, ram, ADC bits, serial ports, ...). On Sun, Apr 2, 2017 at 01:12 am, Raj vu2zap wrote:
How about this Farhan? ??It should do, very economical RF probe!?
?
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If you must have a log amp, I'd make pads for an optional AD8310 (the improved and cheaper AD8307) ?on the main board and have it drive a Nano analog input. ?Make a dandy S meter when not being used to troubleshoot the Bitx or perhaps other gear. ?Those that want it could go out and buy one, or you could make the extra part a buying option at hfsigs. Of course, we'll quickly run out of Nano pins. ?I still like the idea of the Si5351 on the main board, a connector off to the microcrontroller/display of our choice. ?I'd go Teensy 3.2, likely never run out of pins or anything else (mips, flash, ram, ADC bits, serial ports, ...).
On Sun, Apr 2, 2017 at 01:12 am, Raj vu2zap wrote:
How about this Farhan? ??It should do, very economical RF probe!?
?
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Re: New to group -- exploring multiband capabilities
Etherkit has: ?https://www.etherkit.com/rf-modules/si5351a-breakout-board.html
On Sun, Apr 2, 2017 at 08:17 am, cove37 wrote: ?BTW, has anyone successfully dropped a TCXO in place of the oscillator crystal? ?
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anyone have a better idea of a simple 2-3 component rf detector?
- f
Well, not as cheap as the eBay one but could this be useful?
Jer AA1OF Sent from my iPad
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Re: New to group -- exploring multiband capabilities
Ok, that covers my concerns about using all the clock outputs. ?As for the GPS disciplining, I was going to lift the code from QRP Lab's Progrock and use a GPS receiver's 1PPS signal. ?Not cheaper or easier, just a fun way of assuaging the clock freak in me. ?BTW, has anyone successfully dropped a TCXO in place of the oscillator crystal?
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I haven't had reason to play with diode RF probes. ?But here's a quote from ?? suggesting they work well enough at far far lower RF voltages than you might think: ??This one is a bit more sophisticated. It is still a passive probe, but can be calibrated in both output and linearity. Its minimum sensitivity is about 2.3 mVrms input, and in testing so far, has an essentially a flat response from high audio frequencies to about 30 MHz I have not gone beyond that, but it should be good to 100 MHz or so.??The main difference with this RF probe is the fact that it is just about dead on 1:1 RMS input to DC output from 150 mV to past 15V. Again, it should continue to be linear, but I have not tested its voltage response beyond about 26 dB. Most of the RF probe designs out there use the meter's internal resistance in series with a resistor in the RF probe to convert pk-to-pk into rms voltage. ?Careful with that if using an external meter, as they can have an order of magnitude difference in internal resistance. ? Another point often not mentioned is that the probes use that series resistor in the probe plus any stray capacitance inside the meter to form a low pass filter, creating the DC voltage that gets measured.
On Sun, Apr 2, 2017 at 07:53 am, Jerry Gaffke wrote: Actually, a germanium (and likely even schottky) diode probe can work down below 100mv if the current is kept low enough ?
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I hope we can use RF probe with germanium diode when set righting a nonworking BITX by comparing working BITX rig..
On Sun, Apr 2, 2017 at 8:23 PM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote: Actually, a germanium (and likely even schottky) diode probe can work down below 100mv if the current is kept low enough (if the voltmeter is at least a megaohm or so).? That curve is exponential, not two straight lines meeting at a "knee" as we (and LTSPICE) usually think of it.? Below 100mv the results can be repeatable though certainly not linear.? If we use an analog input to the Nano as the voltmeter, then everybody will have about the same voltmeter input impedance to better compare results. > The diode probes work only above 1v levels.
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Actually, a germanium (and likely even schottky) diode probe can work down below 100mv if the current is kept low enough (if the voltmeter is at least a megaohm or so). ?That curve is exponential, not two straight lines meeting at a "knee" as we (and LTSPICE) usually think of it. ?Below 100mv the results can be repeatable though certainly not linear. ?If we use an analog input to the Nano as the voltmeter, then everybody will have about the same voltmeter input impedance to better compare results. > The diode probes work only above 1v levels.
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Chris Viningre
Soundararajan Ra.