Re: Too Much Information?
Messages are all the same URL except the final incrementing integer, will be trivial to create a script to grab them one by one. ?I'm happy enough with the current organization of the group. ?If somebody wants something different, they can go off and create (and administer) it.
I previously wrote:
Would it be possible to do a onetime download of all messages thus far and store it somewhere that I can access it? ?Then I'll turn on daily digests from here on out so I can store them locally as email. ?
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Re: R15 and ADE-1 mixer getting very hot
Sarma,
Insulation breakdown is highly unlikely. William has replaced them and all can't be having the same problem.
When the problem is found you will see how simple it was! this is my experience from many decades.
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At 28-04-2017, you wrote: raj jee,
? There is no heat without ade-1 in place even if the pins 1and 6 are connected with a wire to maintain continuity.
?
Thus it is clear that the trafo inside the mixer covering pins 1&6 is f\getting breakdown (short under real voltage application) to the secondary? and that has middle ground.
Perhaps it would be easy to check placing ade-1 on board and isolating pins 4&6? from ground. later one could connect one by one? pins 4 and 6.
It would show up?
? I finally suppose a case of insulation break down, in real working condition.
regards
? sarma
? vu3zmv
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There is a 45w amp kit sold rather cheap on ebay and aliexpress both.
On Sat, Apr 29, 2017 at 6:40 AM, John Backo via Groups.Io <iam74@...> wrote: Jorge:
Note that you cannot directly substitute a IRF530 for a IRF510.
That is because the input gate capacitance of the 510 is ~180 pF.
and the gate capacitance of the 530 is ~620 pF. That means the input impedance is
considerably different and needs compensation. There is also a difference in
the drain capacitance which will affect the LPF match.
If these are compensated for, with 20v on the drain, the Pk-Pk AC output voltage can be about
36-40v. (The maximum wattage handling ability of the 530 is about 85W.) Note that the heat sink
must be considerably increased in size.
If you want to increase the wattage that much, you should probably opt for a drain voltage of ~36v.
With a suitable matching network and heat sink, that should allow a Pk-Pk voltage of about 70v.
Note that heat is still the biggest enemy and consideration, as it is in any MOSFET PA.
If you are opting for that much power, you probably would be better off designing or building a dual
IRF530 PA. The BITX3B PA would have to be considerably modified, even if the drain voltage were kept low.
You could probably get away with the current design (modified for impedance) with a IRF520, but
probably not a IRF530.
Check the internet; there are many designs out there.
john
AD5YE
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Jorge:
Note that you cannot directly substitute a IRF530 for a IRF510.
That is because the input gate capacitance of the 510 is ~180 pF.
and the gate capacitance of the 530 is ~620 pF. That means the input impedance is
considerably different and needs compensation. There is also a difference in
the drain capacitance which will affect the LPF match.
If these are compensated for, with 20v on the drain, the Pk-Pk AC output voltage can be about
36-40v. (The maximum wattage handling ability of the 530 is about 85W.) Note that the heat sink
must be considerably increased in size.
If you want to increase the wattage that much, you should probably opt for a drain voltage of ~36v.
With a suitable matching network and heat sink, that should allow a Pk-Pk voltage of about 70v.
Note that heat is still the biggest enemy and consideration, as it is in any MOSFET PA.
If you are opting for that much power, you probably would be better off designing or building a dual
IRF530 PA. The BITX3B PA would have to be considerably modified, even if the drain voltage were kept low.
You could probably get away with the current design (modified for impedance) with a IRF520, but
probably not a IRF530.
Check the internet; there are many designs out there.
john
AD5YE
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On 29/04/17 03:19, Jerry Gaffke via Groups.Io wrote:
I prefer to keep it all in one place.
That doesn't work, as things get lost even after just one day. [....] If your radio works, then you can just unsubscribe and
occasionally check
People like it here, and want to stay. Wiki is here: /g/BITX20/wiki Members are expected to Wiki things that they are find. What I'd like is a way to download all messages from the groups.io
website so I can sic an intelligent search tool on them. The
groups.io search bar is nearly unusable.
That's what a www forum is. With the current level of traffic, the group will implode as "unreadable". Too much data flow and not much of it usable after even just a week. Steve ZL1BHD
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? ? ? Greetings to all, what power should I expect from an IRF530 powered by 20 Vdc in the linear of the BITX20 V3B ? Thank you. ? ?Jorge PY2PVT _._ --
? 73 de Jorge PY2PVT
? Campinas SP
? GG67MD
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Re: Too Much Information?
On 29/04/17 05:16, Arv Evans wrote: [....] If we were to narrow the discussion parameters it might
decrease the value of the group as a comprehensive repository of BITX
information of all types. It needs to move to a forum. S
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Re: Bitx40 vs the antenna beast
I. too, am warring with the "antenna beast". I live with my parents, and my dad doesn't want me running coax cables out through window panel feed-throughs or drilling holes in the upstairs walls, and the metal-framed windows are designed in such a way as to pinch a feed-through cable made of flat lead.
My solution will be to make a folded dipole, run around the wall just under the ceiling in my bedroom, and made of 300 ohm flat lead (I have 50 feet of the stuff), with the "legs" 20-1/2 feet long each (I have 41 linear feet of wall in my room). I will be using a 6:1 balun to impedance match (50 ohms out from the radio to the 300 ohm antenna), with an automatic antenna tuner (either my Elecraft T1 or one of my old but trusty LDG AT-11 tuners) between the rig and the balun. Probably won't work much past 40 meters, but it's better than nothing at all!
Rich KC8MWG
On Friday, April 28, 2017 6:13 PM, richard kappler <richkappler@...> wrote:
Fred,
You are a gentleman and a scholar, that is exactly the type of guidance I was looking for!
Cheers, Richard W2KAP?
On Apr 28, 2017 6:02 PM, "Dr Fred Hambrecht" < AAR4MI@...> wrote: Use the MFJ to determine where the antenna is resonant. If the frequency is below 7.285 decrease the ?amount of coil and recheck. Conversely if it is resonate above 7.286 you will have to add coil. ? v/r Fred W4JLE ? ? So I'm a new ham (General), as I've said before, and aside from a VHF/UHF HT, the BitX is my first (and presently only) radio. I'm in an apartment, so antenna choices are severely limited. I am currently running my BitX through a MFJ-1622, which is tapped coil 1/4 wave apartment antenna with a 5 foot whip and a counterpoise. ?(? ). I've NEVER been able to hear anything but static on my BitX40, and have done much troubleshooting, finding nothing amiss thus far (on the second one anyway, the first one I built is another story for another day). I took a wafg and figured it to be the antenna, ordered the parts for Jack's antenna analyzer, most of which still aren't here. Impatient as I am, I've sprung for an MFJ-259C antenna analyzer, which arrived about an hour ago, and sure as shootin', my antenna appears to be VERY out of whack.impedance is about 90 ohms, SWR up at 13.5 at freq 7.285. And now the question: Is this most likely the reason I've been able to hear nothing and no one has been able to hear me? Then I, of course, have to go OT a bit: Any suggestions as to how to adjust this antenna to something reasonable? Near as I can figure, it has three mechanical adjustments: placement of tap on coil, whip length, counterpoise length. I will, of course, spend the weekend adjusting everything, one thing at a time, small adjustments, until I figure it out, but if anyone has the antenna knowledge to give me a little guidance, it would sure save some time. If it's not the antenna, you'll be hearing from me. I've been trying to get on HF for about 2 months now. I've got me an itch that demands scratching! -- In any given circuit, the most expensive part will always sacrifice itself to protect the fuse.
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Re: Bitx40 vs the antenna beast
Fred,
You are a gentleman and a scholar, that is exactly the type of guidance I was looking for!
Cheers, Richard W2KAP?
On Apr 28, 2017 6:02 PM, "Dr Fred Hambrecht" < AAR4MI@...> wrote: Use the MFJ to determine where the antenna is resonant. If the frequency is below 7.285 decrease the ?amount of coil and recheck. Conversely if it is resonate above 7.286 you will have to add coil. ? v/r Fred W4JLE ? From: [email protected] [mailto:[email protected]] On Behalf Of richard kappler
Sent: Friday, April 28, 2017 2:24 PM
To: [email protected]
Subject: [BITX20] Bitx40 vs the antenna beast ? So I'm a new ham (General), as I've said before, and aside from a VHF/UHF HT, the BitX is my first (and presently only) radio. I'm in an apartment, so antenna choices are severely limited. I am currently running my BitX through a MFJ-1622, which is tapped coil 1/4 wave apartment antenna with a 5 foot whip and a counterpoise. ?(? ). I've NEVER been able to hear anything but static on my BitX40, and have done much troubleshooting, finding nothing amiss thus far (on the second one anyway, the first one I built is another story for another day). I took a wafg and figured it to be the antenna, ordered the parts for Jack's antenna analyzer, most of which still aren't here. Impatient as I am, I've sprung for an MFJ-259C antenna analyzer, which arrived about an hour ago, and sure as shootin', my antenna appears to be VERY out of whack.impedance is about 90 ohms, SWR up at 13.5 at freq 7.285. And now the question: Is this most likely the reason I've been able to hear nothing and no one has been able to hear me? Then I, of course, have to go OT a bit: Any suggestions as to how to adjust this antenna to something reasonable? Near as I can figure, it has three mechanical adjustments: placement of tap on coil, whip length, counterpoise length. I will, of course, spend the weekend adjusting everything, one thing at a time, small adjustments, until I figure it out, but if anyone has the antenna knowledge to give me a little guidance, it would sure save some time. If it's not the antenna, you'll be hearing from me. I've been trying to get on HF for about 2 months now. I've got me an itch that demands scratching! -- In any given circuit, the most expensive part will always sacrifice itself to protect the fuse. 
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Re: Bitx40 vs the antenna beast
Use the MFJ to determine where the antenna is resonant. If the frequency is below 7.285 decrease the ?amount of coil and recheck. Conversely if it is resonate above 7.286 you will have to add coil. ? v/r Fred W4JLE ?
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From: [email protected] [mailto:[email protected]] On Behalf Of richard kappler
Sent: Friday, April 28, 2017 2:24 PM
To: [email protected]
Subject: [BITX20] Bitx40 vs the antenna beast ? So I'm a new ham (General), as I've said before, and aside from a VHF/UHF HT, the BitX is my first (and presently only) radio. I'm in an apartment, so antenna choices are severely limited. I am currently running my BitX through a MFJ-1622, which is tapped coil 1/4 wave apartment antenna with a 5 foot whip and a counterpoise. ?(? ). I've NEVER been able to hear anything but static on my BitX40, and have done much troubleshooting, finding nothing amiss thus far (on the second one anyway, the first one I built is another story for another day). I took a wafg and figured it to be the antenna, ordered the parts for Jack's antenna analyzer, most of which still aren't here. Impatient as I am, I've sprung for an MFJ-259C antenna analyzer, which arrived about an hour ago, and sure as shootin', my antenna appears to be VERY out of whack.impedance is about 90 ohms, SWR up at 13.5 at freq 7.285. And now the question: Is this most likely the reason I've been able to hear nothing and no one has been able to hear me? Then I, of course, have to go OT a bit: Any suggestions as to how to adjust this antenna to something reasonable? Near as I can figure, it has three mechanical adjustments: placement of tap on coil, whip length, counterpoise length. I will, of course, spend the weekend adjusting everything, one thing at a time, small adjustments, until I figure it out, but if anyone has the antenna knowledge to give me a little guidance, it would sure save some time. If it's not the antenna, you'll be hearing from me. I've been trying to get on HF for about 2 months now. I've got me an itch that demands scratching! -- In any given circuit, the most expensive part will always sacrifice itself to protect the fuse.
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I'll be here in the PNW, if I don't hear anything I'll call CQ BITX -- Ryan Flowers W7RLF?
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OK, BITX QSO night on Sunday, April 30 at 9pm Eastern, on 7195. Call cq and say you are running BITX QRP. Keep calling cq frequently, and listen very closely for responses, they may be faint.
If you get a big gun to respond (over 10 Watts), ask him to relay to any other rigs that he hears. Watch this forum if there is QRM on 7195. We will coordinate an alternate frequency here. (Proposed alternate: 7188)
Please report BITX to BITX QSOs made here.
Lets hope for good propagation!
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Re: Too Much Information?
Am hoping one of the other admins could look into this. ?Having learned to program on a PDP-8, ?I agree it would be huge. ?The kids today would not. ?When we hit the GByte limit a few months ago, it was images that took up most of that, messages are on the order of a couple hundred MBytes. ?At current prices per GByte for a USB flash drive, that's about $0.10 worth. ?And could transfer in seconds for those with a decent internet connection. ?
?
On Fri, Apr 28, 2017 at 11:19 am, Arv Evans wrote:
The amount of stored data since the first BITX would be huge because it includes many discussions as each new design became available. ?BITX20, BITX20A, BITX17A, MKARS-80, BITX40A, BITX-V3, Minima, BINGO, BITX-40, and many more designs are represented in the history.
?
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Re: R15 and ADE-1 mixer getting very hot
Curious as to where the schematic using the ADE-1 is. Mike K5ESS ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Mvs Sarma
Sent: Friday, April 28, 2017 10:33 AM
To: [email protected]
Subject: Re: [BITX20] R15 and ADE-1 mixer getting very hot ? ?There is no heat without ade-1 in place even if the pins 1and 6 are connected with a wire to maintain continuity.
? Thus it is clear that the trafo inside the mixer covering pins 1&6 is f\getting breakdown (short under real voltage application) to the secondary? and that has middle ground. Perhaps it would be easy to check placing ade-1 on board and isolating pins 4&6? from ground. later one could connect one by one? pins 4 and 6. It would show up? ?I finally suppose a case of insulation break down, in real working condition. ? On Fri, Apr 28, 2017 at 6:57 PM, William Hemmingsen <lee.hemmingsen@...> wrote: 2-5 - .216v in both direction ? On Fri, Apr 28, 2017 at 8:37 AM, Raj vu2zap <rajendrakumargg@...> wrote: William,
Please check the continuity of your ADE-1ASK again.
1-6 - 0
2-5 - Diode check both polarity should be same reading
3-4 - 0
My guess is continuity between these pins but not between others.
I have a few but could not find it to confirm, maybe someone could confirm the above!
With the ADE not soldered, shine a bright light from the component side and check for shorts (most likely) between
4/5 and 6, trace all the way to Q7. Check if there is a short to ground at collector of Q7 or the track leading to it
from ADE pin 6.
Put the ADE back, without power and check for short to ground from ADE pin 1 and 6.
My guess is that only a short to ground between ADE pin 6 to Q7 can cause the ADE to heat up along with R15!
73
Raj, vu2zap
1-2 19k ohms 1-3,4,5 open 1-6 0 ohms (RF Primary) 2-3 42k ohm 2-4 open 2-5 19k ohms <<<<<<<<<<<<< diode 2-6 19k ohms 3-4 0 ohms (LO Primary) 3-5 open 3-6 open 4-5/6 open ?? Pin 2 & 3 both go to blocking capacitors c18,c19,c11,c15 on RF & IF Amps.?? I tested these pins to ground on the board and they are open as expected.?? This means the short must be in the ADE-1 itself, and only when power is applied. Looking at the bottom of the ADE-1, there are 2 wires on pin 1.?? I expect these are RF primary and secondary ground. This is very strange W4WHL ?
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Thanks for reporting Dave,
Yes, it appears there is some variability between the BITX40 sets. Mine
performs best at 4mA, yours may need another value.
I suggest to use v1.08 as it allows you to easily change the VFO drive
level via the Function Button. Tune in to the birdie, switch between
different drive level settings and hear the result intantaneously.
73, Allard PE1NWL
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On Fri, April 28, 2017 21:18, David Fannin wrote: Allard,
I've tried 1.01 with 2MA, and 1.06 with 4MA. ??The 7.199 birdie was much
louder with 4MA vs. 2MA. ??I will also see if if I can see what's going on
with the mixer/LO via a spectrum analyzer.??
I will try the other levels this weekend and report back.
Dave.
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Successful diagnosis by tapping circuit board
I was having a lot of difficulty with my bitx40, the audio would get louder, then softer. I have done a number of mods to the board, and added features to the point that it no longer worked right.
I was trying to figure out how to diagnose the problems, and one day, I happened to tap the case and noticed that the audio changed.? I opened up the case and started gently tapping various parts of the board with my finger. Within minutes, I found an area of the board with resistors that would respond to a tap with a change in audio. I also found that tapping T1 would change the audio.? I fired up a soldering iron and reheated the resistor connections.? That made a big difference. Then I resoldered the T1 wires and gently moved the wires until there was no audio change while tapping. So far, the radio seems to work as it should.? Just another diagnostic method to identify problem areas.
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Re: Bitx40 vs the antenna beast
Richard,
For RX only, try as much wire as you can string about.? Won't work
for TX but should be better for picking up signals. Ask around for
the frequency and time for nets in your area and you should be
able to determine if you can pick anything up. Here on the west
coast we have a noon net that runs for 3+ hours a day with
stations from all over the west so one can easily figure out how
your antenna is hearing.
Good luck and 73,
Jonathan
On 4/28/2017 11:24 AM, richard kappler wrote:
toggle quoted message
Show quoted text
So I'm a new ham (General), as I've said before,
and aside from a VHF/UHF HT, the BitX is my first (and presently
only) radio. I'm in an apartment, so antenna choices are
severely limited. I am currently running my BitX through a
MFJ-1622, which is tapped coil 1/4 wave apartment antenna with a
5 foot whip and a counterpoise. ?(?
).
I've NEVER been able to hear anything but static on my
BitX40, and have done much troubleshooting, finding nothing
amiss thus far (on the second one anyway, the first one I
built is another story for another day). I took a wafg and
figured it to be the antenna, ordered the parts for Jack's
antenna analyzer, most of which still aren't here. Impatient
as I am, I've sprung for an MFJ-259C antenna analyzer, which
arrived about an hour ago, and sure as shootin', my antenna
appears to be VERY out of whack.impedance is about 90 ohms,
SWR up at 13.5 at freq 7.285.
And now the question: Is this most likely the reason I've
been able to hear nothing and no one has been able to hear me?
Then I, of course, have to go OT a bit: Any suggestions as
to how to adjust this antenna to something reasonable? Near as
I can figure, it has three mechanical adjustments: placement
of tap on coil, whip length, counterpoise length.
I will, of course, spend the weekend adjusting everything,
one thing at a time, small adjustments, until I figure it out,
but if anyone has the antenna knowledge to give me a little
guidance, it would sure save some time.
If it's not the antenna, you'll be hearing from me. I've
been trying to get on HF for about 2 months now. I've got me
an itch that demands scratching!
73, Richard
--
W2KAP
In any given circuit, the
most expensive part will always sacrifice itself to
protect the fuse.
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Allard, I've tried 1.01 with 2MA, and 1.06 with 4MA. ?The 7.199 birdie was much louder with 4MA vs. 2MA. ?I will also see if if I can see what's going on with the mixer/LO via a spectrum analyzer.? I will try the other levels this weekend and report back. Dave.
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Raj vu2zap
Allard PE1NWL
Dave F
Craig Wadsworth