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I haven't had a chance to poke at the ubitx v4 lately. I'm fixing up a bitx40 for a friend and I'm almost done with that!
-a
On Thu, 25 Apr 2019 at 18:53, digger AB3XU < digger@...> wrote: Yes, after much trial and tribulation I'm pretty happy, and confident, with my freq and bfo calibration.
-- digger AB3XU
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Yes, after much trial and tribulation I'm pretty happy, and confident, with my freq and bfo calibration.
-- digger AB3XU
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To those of you with V4 issues have you done a BFO calibration? I expect the factory stock to be acceptable but it never hurts to ask at this point!
Adrian did you ever get a chance to take those measurements for me :)
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Tim Keller - KE2GKB
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Sorry, Tim, I do have another V5 but it is still in the box it was shipped in.
Just to be clear here are some notes on how I? tested:
* signal generator is a Sark 110 using an unmodulated carrier, mostly at 7.1MHz
* verified output level of Sark110 with a Siglent spectrum analyzer.?
* vol-hi measurements are Vp-p using a hitachi o-scope.
* vol-hi measurements are taken at AGC board
* AGC vol-hi?is connected to R70 with an unshielded wire.
* the ubitx case is made with pcb, but the top has been open for testing.
* the noise on the vol-hi I see on the o-scope is a very regular waveform. I see it with the ubiitx turned off and the antenna terminted with 50¦¸.
* noise may be o-scope/probe problem? The level was reduced when I swapped probes?
l'd like to help more, but time is very limited for at least the next 3 weeks (fulltime job and last couple of weeks in a graduate program)
? Since I have at least a little bit of test equipment, once my time is freed up there is the possibility of hooking up with anyone else who might be in the Philadelphia area with a?ubitx to do some testing.
73, digeer AB3XU
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Yes I know whats wrong.
You need to look at the port # your using. Your connected to the
wrong Port #.
Open your Device Manager and click on ports. The port you need is
the one that says? "USB-SERIAL CH340 (com#). The Pound sing in the
port # you need to select in the Manager program in uBITx.
hen it will work
WB8LGA
Charles Beener
On 4/16/2019 2:09 PM, KE2GKB via
Groups.Io wrote:
toggle quoted message
Show quoted text
If I could ask for the same measurements that
digger took that would be great.?
The solution here is going to be either modding
the ubitx to fix the audio issue or adding an amp for the
boards that need it.? The attenuation range is based on how
much af drive is given to the circuit. If you read nd6t's
original articles you can see why the values reported by
digger are just not cutting it!
I'm personally just fustrated that some of you
will have issues with our product. While it is a kit it's
meant to just work. So thank you all for the support!
On Tue, Apr 16, 2019, 1:10 PM
Adrian Chadd < adrian@...> wrote:
i have a ubitx v4 with your AGC board
installed. I also live in an amusingly noisy environment and
I have relevant testing kit. :-P
Let me know what you'd like and I'll go see if I can
take some measurements for you.
-adrian
On Tue, 16 Apr 2019 at
09:26, KE2GKB via Groups.Io <tkeller= [email protected]>
wrote:
Digger do you have any other uBitxs? I currently do not
have a good known noise source (Working on it! but alas
the day job has its priority :( ) So it is currently out
of my capability to make comparison measurements. I do
know that those numbers are on the order of about 3x
lower then they should be based on the non scientific
measurements I have taken on my unit.
--
Tim Keller - KE2GKB
--
Tim Keller - KE2GKB
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Awesome,
That still said if anyone has a V3 with it and the appropriate equipment that would be amazing.
--
Tim Keller - KE2GKB
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hi,
ok. I've fixed (hopefully!) the switch wiring for the AGC and I'll go take some measurements soon.
-adrian
On Tue, 16 Apr 2019 at 11:09, KE2GKB via Groups.Io <tkeller= [email protected]> wrote: If I could ask for the same measurements that digger took that would be great.? The solution here is going to be either modding the ubitx to fix the audio issue or adding an amp for the boards that need it.? The attenuation range is based on how much af drive is given to the circuit. If you read nd6t's original articles you can see why the values reported by digger are just not cutting it!
I'm personally just fustrated that some of you will have issues with our product. While it is a kit it's meant to just work. So thank you all for the support!
On Tue, Apr 16, 2019, 1:10 PM Adrian Chadd < adrian@...> wrote: i have a ubitx v4 with your AGC board installed. I also live in an amusingly noisy environment and I have relevant testing kit. :-P
Let me know what you'd like and I'll go see if I can take some measurements for you.
-adrian
On Tue, 16 Apr 2019 at 09:26, KE2GKB via Groups.Io <tkeller= [email protected]> wrote: Digger do you have any other uBitxs? I currently do not have a good known noise source (Working on it! but alas the day job has its priority :( ) So it is currently out of my capability to make comparison measurements. I do know that those numbers are on the order of about 3x lower then they should be based on the non scientific measurements I have taken on my unit.
--
Tim Keller - KE2GKB
--
Tim Keller - KE2GKB
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If I could ask for the same measurements that digger took that would be great.? The solution here is going to be either modding the ubitx to fix the audio issue or adding an amp for the boards that need it.? The attenuation range is based on how much af drive is given to the circuit. If you read nd6t's original articles you can see why the values reported by digger are just not cutting it!
I'm personally just fustrated that some of you will have issues with our product. While it is a kit it's meant to just work. So thank you all for the support!
On Tue, Apr 16, 2019, 1:10 PM Adrian Chadd < adrian@...> wrote: i have a ubitx v4 with your AGC board installed. I also live in an amusingly noisy environment and I have relevant testing kit. :-P
Let me know what you'd like and I'll go see if I can take some measurements for you.
-adrian
On Tue, 16 Apr 2019 at 09:26, KE2GKB via Groups.Io <tkeller= [email protected]> wrote: Digger do you have any other uBitxs? I currently do not have a good known noise source (Working on it! but alas the day job has its priority :( ) So it is currently out of my capability to make comparison measurements. I do know that those numbers are on the order of about 3x lower then they should be based on the non scientific measurements I have taken on my unit.
--
Tim Keller - KE2GKB
--
Tim Keller - KE2GKB
|
i have a ubitx v4 with your AGC board installed. I also live in an amusingly noisy environment and I have relevant testing kit. :-P
Let me know what you'd like and I'll go see if I can take some measurements for you.
-adrian
On Tue, 16 Apr 2019 at 09:26, KE2GKB via Groups.Io <tkeller= [email protected]> wrote: Digger do you have any other uBitxs? I currently do not have a good known noise source (Working on it! but alas the day job has its priority :( ) So it is currently out of my capability to make comparison measurements. I do know that those numbers are on the order of about 3x lower then they should be based on the non scientific measurements I have taken on my unit.
--
Tim Keller - KE2GKB
|
Digger do you have any other uBitxs? I currently do not have a good known noise source (Working on it! but alas the day job has its priority :( ) So it is currently out of my capability to make comparison measurements. I do know that those numbers are on the order of about 3x lower then they should be based on the non scientific measurements I have taken on my unit.
--
Tim Keller - KE2GKB
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Lee I sent it over. The updated instructions are in the same download area on the kit-projects website. -- David
?N8DAH
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Hi David, would you please email me the updated switch diagram for my agc I just received from you a week or two ago.? I did question the supplied diagram.? thanks? Lee ? wb3acc@... ?? 73
On April 14, 2019 at 11:55 PM N8DAH <Dherron@...> wrote:
I have restocked mic's, paddles and AGC's. The AGC doc's have been updated with the correction for the DP3T. 73
--
David ?N8DAH
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I have restocked mic's, paddles and AGC's. The AGC doc's have been updated with the correction for the DP3T.
73
--
David
?N8DAH
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Tim, here's what I got this evening. Hopefully the numbers are good. They are similar to what I posted yesterday. The Vol-Hi measures are p-p done on an o-scope. There was a fair amount of noise at Vol-Hi maybe about 10mVp-p. It was tough getting a good connection.
Input?????? ADC???? A7(Vdc)??? Vol-hi(Vp-p)
-73dBm??????? 2???? 0.02??????? 20mV
-63dBm?????? 59???? 0.303?????? 72mV
-53dBm????? 158???? 0.795?????? 240mV
-43dBm????? 196???? 0.981?????? 660mV
I had to do the Vol-Hi measurements a second time after I realized it wouldn't work with the ADC on. (My turn to say, DOH)
--digger AB3XU
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I am under the impression the documentation has been fixed.
That aside. R70 is a good place to be taking the audio from no issues there.
I am fairly confident the issue stems from the drive level on the v4's being lower then the agc expects. I think the simple solution is going to be add another amplifier stage before the audio in on the AGC but not having a board my self it is hard to test this.
Digger could I get the measurements of Vol-High with those same measurements?
--
Tim Keller - KE2GKB
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Thanks also, Tim, for these explanations. With the correct wiring instructions most of these questions didn't need to be answered.
As far as vol-high I'm taking it from the via hole at R70 which is just a few inches from the agc board.
73, digger
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Hi!
Thanks to everyone for digging into this. I just added the AGC mod to my board and wondered about this behaviour. I'd love to know how to tweak the board to work on a v4 bitx.
Thanks!
-adrian
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Sorry missed the questions in the photograph.
1) Off and Ground are the same. To turn the circuit off you need to ground common. This removes the audio input to the circuit, and thusly turns off the AGC. This was marked this way in part due to what is in answer 3.
2) The official Wire up instructions say that Yellow is VolHigh, That is what our documentation is based on.
3) the D designations are in that single photo as it is a clip out of the schematic. The prefix was used for clarity when reading the schematic. The image was copied from the schematic and used with out editing. Yes D_Com and Common are on the same Net.
--
Tim Keller - KE2GKB
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Hey Digger,
Thanks for the feed back. So you are actually the second person to reach out to us about this. We realized this afternoon that the documentation was in error. I supplied david with the wiring information incorrectly. I had the switch upside down in my install DOH!
The simple fix is to flip the switch over, It is correct with the notch facing down. The directions being supplied going forward have the information fixed. With an adjusted wire up to solve the issue. Our sincerest apologies.
As for the low S-Meter issue. What version uBitx do you have? Is it a v4? It was brought to my attention after production started that the v4 has a lower audio drive then the v3 models. The original circuit this was based off of is tuned for the v3's I am actively working on a fix for this. Your numbers are actually super helpful.
KE2GKB
--
Tim Keller - KE2GKB
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Hey,
I've installed the uBITX AGC board per the instructions and it just doesn't seem like its working correctly. I feel like I've gone round circles trying to make sense of it all.
In part I wonder if some kits were shiped with a lot of switches that are configured differently? I've attached a drawing of continuity checks of the supplied switch and it doesn't seem to make sense with the documentation.
I've also tried to understand the logic of the switch based on schematics I've found on ND6T's website and can't figure it out. Is there a schematic available for this particular board? I think a lot of my questions would be answered with a schematic.
Without going too far down the rabbit hole, here are two points to begin with:
* AGC is off with the switch in the up position (NOT down). This was determined by measuring the voltage on the S-METER Output; it drops to 0.0 volts with the switch in the up position.
* The voltage measurement at S-METER Output on the AGC board is very low:
??? -73dBm (S9):??? 0.02V
??? -53dBm (S9+10): 0.25
??? -63dbm (S9+20):? 0.78
??? This is using a Sark-110 for an input; the level was verified with a Siglent SSA 3021X. The Sark's lowest output is -73dBm. All measurements were made with S-METER Output attached to A7 of the Raduino.
Also attached is a drawing of how it's all wired up.
73, digger AB3XU
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digger AB3XU
N8DAH
