You've got a 'comfort zone' with phones and mods, Chris. I'm still working on it headed that way too, but pot (preset or on back) -res-cap to vol pot gives adjustment available to individual preference (which may vary with mood/environment) overall. Just looking ahead here ...
73 de ZL2DEX
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I been doing doing the audio mods my 3 sets are sorted now the tx audio mod done on my 80m set others to do tx power I need to sort out 80 m I see 4 watt max rf on the 40m set I am seeing up to 15w and on 60m? 3? watt all with 12.8v time to pack up for today chris
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I only use headphones my bitx's all have AGC fitted and rf gain fitted? just keep the volume backed down
On 20 Nov 2017 20:43, "Dexter N Muir" < dexy@...> wrote: It works alright, but different impedances between speaker and phones means different *relative* volume levels. What's fine on the speaker will likely blast your ears off on the phones. I push for a resistive divider and cap to the top of the volume control. Not sure of values - personal preference, maybe a pot?
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Thanks for the updated schematic!? What did you find that led to the change in the 45 MHz band pass filter (should the original LC network not be used?)?? Also - is it safe to assume that the pair 2N2219As were changed to 4 2N3904s in the driver to simplify or standardize the parts list?
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On Fri, Oct 6, 2017 at 01:10 pm, Ashhar Farhan wrote:
I am plodding through the write-up part of the new version. in the meantime, here is just the schematic. not very different.
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It works alright, but different impedances between speaker and phones means different *relative* volume levels. What's fine on the speaker will likely blast your ears off on the phones. I push for a resistive divider and cap to the top of the volume control. Not sure of values - personal preference, maybe a pot?
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Re: Strange tuning problem on BitX-40
Yep the one that was fitted cost me ?8 each I replaced it with one that cost ?4 my bitx60 is fixed and working how it should?
On 20 Nov 2017 20:15, "Jerry Gaffke via Groups.Io" <jgaffke= [email protected]> wrote: There's good and bad, China makes some truly quality stuff.
But with everybody searching ebay or amazon and then selecting only on price,
the manufacturers there will oblige.?
The only way to weed out the bad from the good is to check the reviews
or otherwise see what other buyers are having success with.
But reviews are not always reliable or knowledgeable,
and the seller my substitute something similar when stocks run low.?
The alternative is to buy a name brand part from a trusted vendor.
The cheapest I see on Mouser for a Bourns 10 turn pot quantity one is $13.68 plus shipping.
Jerry
On Mon, Nov 20, 2017 at 11:47 am, chris gress wrote:
OK I will check it out they came from amazon made in China rubbish?
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Re: Strange tuning problem on BitX-40
There's good and bad, China makes some truly quality stuff.
But with everybody searching ebay or amazon and then selecting only on price,
the manufacturers there will oblige.?
The only way to weed out the bad from the good is to check the reviews
or otherwise see what other buyers are having success with.
But reviews are not always reliable or knowledgeable,
and the seller my substitute something similar when stocks run low.?
The alternative is to buy a name brand part from a trusted vendor.
The cheapest I see on Mouser for a Bourns 10 turn pot quantity one is $13.68 plus shipping.
Jerry
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On Mon, Nov 20, 2017 at 11:47 am, chris gress wrote:
OK I will check it out they came from amazon made in China rubbish?
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Re: Strange tuning problem on BitX-40
Yep I know I am going to fit a new one I have 3 extras in my box when it rolls the frq the voltage on the wiper drops low?
On 20 Nov 2017 19:55, "Michael Davis" < maddmd818@...> wrote: Don't forget that the 10 turn pots solder tabs are different than normal 1 turn pots. The center tab is NOT the wiper.
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Re: Strange tuning problem on BitX-40
On Mon, November 20, 2017 20:55, Michael Davis wrote: Don't forget that the 10 turn pots solder tabs are different than normal 1
turn pots. The center tab is NOT the wiper. See 73 Allard PE1NWL
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On Mon, November 20, 2017 19:09, Guy N7BIR wrote: Allard, now that I?€?ve updated the latest BitX40 firmware, is there any
reason to keep the original Cailbrate switch?
The software still supports the original calibrate switch, just for reasons of backward compatibility (so that the software still works on a stock BitX40 board without any mods). But if you have meanwhile installed the Function Button then you obviously don't need the calibrate switch anymore, because with the FB you can perform calibration from the SETTINGS menu. 73 Allard PE1NWL
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Re: Strange tuning problem on BitX-40
Don't forget that the 10 turn pots solder tabs are different than normal 1 turn pots. The center tab is NOT the wiper.
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Re: Strange tuning problem on BitX-40
OK I will check it out they came from amazon made in China rubbish?
On 20 Nov 2017 19:45, "Jerry Gaffke via Groups.Io" <jgaffke= [email protected]> wrote: Put a voltmeter between the wiper pin of the pot and the ground pin.
See if the voltage jumps around erratically as you turn the knob
Easy to imagine it might be failing.
Especially if you found it on ebay for less than a dollar.
Jerry
On Mon, Nov 20, 2017 at 11:26 am, chris gress wrote:
Talking of strange tuning my 60m bitx is playing up I have loads of places on my 10turn pot where the frq jumps around anyone think the multi turn pot is at fault chris?
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Re: Strange tuning problem on BitX-40
Put a voltmeter between the wiper pin of the pot and the ground pin.
See if the voltage jumps around erratically as you turn the knob
Easy to imagine it might be failing.
Especially if you found it on ebay for less than a dollar.
Jerry
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On Mon, Nov 20, 2017 at 11:26 am, chris gress wrote:
Talking of strange tuning my 60m bitx is playing up I have loads of places on my 10turn pot where the frq jumps around anyone think the multi turn pot is at fault chris?
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Re: Strange tuning problem on BitX-40
Talking of strange tuning my 60m bitx is playing up I have loads of places on my 10turn pot where the frq jumps around anyone think the multi turn pot is at fault chris?
On 20 Nov 2017 14:27, "M Garza" < mgarza896@...> wrote: Hi David, Let us know if you plan on trashing the rig.? Someone will probably offer to buy it.
Thanks
Marco - KG5PRT
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Mike could be right, could work fine at 7mhz with longer IRF510 leads. But an RF amp like that can be awfully unpredictable. A bit too much inductance in the gate lead and it might go into oscillation at VHF, for example.? The source pin of the IRF510 has to be nailed hard to ground. The drain should be kept clear of anything having to do with the gate. As Ryan's plots have shown, performance is already falling off a bit at 7mhz on a stock Bitx40v3. I'd suggest you measure DC power into the IRF510 drain and RF power out to the antenna before and after the mod for a known signal (perhaps use Allard's CW mode). If power out and efficiency remain as they are on a stock rig, that's probably good enough. And take a look at this post from Allison: ? ?? /g/BITX20/message/22597Good luck. Jerry, KE7ER
On Mon, Nov 20, 2017 at 10:06 am, Mike Yancey wrote:
Totally reasonable, totally feasible.
You know, if you were carrying it a little distance, like 3 inches (7.6cm) you? could have Pin 2 travel back via a bit of short, RG174 coax, shield grounded (say, even to pin 3).
But - one inch - meh, don't bother, straight leads, no worries.
Mike Y, KM5Z (Darn! I need to make time for Sunday's net...)
Dallas, Texas
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Allard, now that I¡¯ve updated the latest BitX40 firmware, is there any reason to keep the original Cailbrate switch?
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Totally reasonable, totally feasible.
You know, if you were carrying it a little distance, like 3 inches (7.6cm) you? could have Pin 2 travel back via a bit of short, RG174 coax, shield grounded (say, even to pin 3).
But - one inch - meh, don't bother, straight leads, no worries.
Mike Y, KM5Z (Darn! I need to make time for Sunday's net...)
Dallas, Texas
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Re: Strange tuning problem on BitX-40
Hi David, Let us know if you plan on trashing the rig.? Someone will probably offer to buy it.
Thanks
Marco - KG5PRT
On Nov 20, 2017 2:29 AM, "David Holland" < g4ldt@...> wrote:
Hi Raj,
I tried the sketch you sent but it would not compile.? I have ordered another Raduino.? If that doesn't work the whole thing is going in the bin!!!? Life is too short.
Thanks for your help,
David
On 20/11/2017 03:25, Raj vu2zap wrote:
Try that sketch I sent a link earlier. It displays the pot position on the 2nd line.
Raj
At 19/11/2017, you wrote:
Seems the Raduino is mostly working.
Could be his main computer has some issue with getting that serial monitor to work.
Dumping readings to the LCD might be more reliable.
On Sun, Nov 19, 2017 at 05:46 am, Allard PE1NWL wrote:
- On Sun, November 19, 2017 12:50, David Holland wrote:
- I have uploaded the test sketch Allard and followed your instructions.
- A window does indeed pop up. It is empty. Nothing further happens!
- I suspect there may be some hardware issue on the Raduino board.
- You should at least get something out on the serial monitor.
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Yes I've made some local contacts with good reports back. No DX as yet, but had a West Papua (YC9) return my call, but we were unable to complete the QSO. That's 1200 km from my QTH in Darwin, Northern Territory. My antennas are my limitation and I am working on improving that aspect.
Thanks all again.
73
Phil
VK8VWA
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Phil,
Mine had a bad contact at the power connector. Things looked normal but when you tx nothing out! A pull and push of the
final power jack solved the problem!
Raj
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At 20/11/2017, you wrote: Thank you all for your helpful suggestions.
Now I warned you I was a complete novice and it turns out that I hadn't damaged the rig at all but instead had neglected to reconnect the wire to the PA connector. The little guy had hidden himself under the board when I reassembled it. Plugged it back in and it all works a treat.
*hangs head in embarrassment*
73
Phil
VK8VWA
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Allard PE1NWL
Raj vu2zap