Re: Templates for China EF01 Electronic Plastic Shell Project Case for a BITX40
Interesting, but I have used a Radio Shack "knibbling tool"?
? (now from Amazon) and was able to cut steel with it. Aluminum cuts like butter, and plastic like air.
I used some PCB for mine. Or you can go to a hardware store and get some aluminum and make a new panel. The steel one is hard to work with.?
mike
AI4NS
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I have a bitx 40 but no display
Dave are you looking for just the LCD, which is a common 1602 5v unit, or the complete Raduino? --
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Re: Brand new uBiTX v5.0 quality issue ?
My V5 board which I received in July 2019 had exactly the same problem: RV2 or RV3 (don't rememember which one)
was bad.
Since no damage was visible, it took some time to find the cause for the low power output.
I first thought one of the IRF510 was dead and changed it, but this did not help.
After measuring the bias of both MOSFETS then, I noticed that one poti could only be adjusted to about 1,5V (i think). If you turned further,
the voltage just disappeared.
When i desoldered the poti, i noticed that one pin was broken. So I think that the path on which the wiper glided become uneven and the poti lifted
itself when turning to much to the left so that the contact of the torn pin got interrupted.
After exchanging the poti to a new one, it worked immediately :-)
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Hi, ????? I have a bitx 40 but no display,i wonder if anyone can point me in the right direction ive tried to email hf igs but had no replies,does anyone have spare i can buy please.Regards Dave G0AYD QTHR AND . Thanks in anticipation.. ??
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Fw: [JackAl] uBitx v6 compatibility?
George:
We don't have a V6 yet, but since we replace the entire radino board anyway, I would think it should.? Let's put it this way, I will give someone a JackAl board if they agree to test it on a V6 board and write up a timely short report on it for distribution here. If you want to test it, please tell me the kind of building/test equipment you have. (Al and I are starting the PCB's for the projects in the book and it's going to keep us busy for a while.)
Jack, W8TEE
On Tuesday, December 17, 2019, 4:17:30 PM EST, n2apb <n2apb@...> wrote:
Is JackAl compatible with the new v6 uBitx board?
73, George N2APB
-- Jack, W8TEE
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Yellow Brick Road?
-- ZL2DEX
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You mean "stairway to heaven"?
I drive by this every day:
It's at the Domino's world headquarters in Ann Arbor, MI, and is a 'disguise' cell phone tower.
73,
-- Dave, N8SBE
-------- Original Message --------
Subject: Re: [BITX20] New tower
From: "GM4CID" < gm4cid@...>
Date: Tue, December 17, 2019 9:15 am
To: [email protected]
Makes me think of the Led Zepplin song.
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Re: ?BITX & QRP labs 50W PA
Mark,
For SSB high idle current are not a factor (unless unrealistically high) as
the average current is likely going to be higher and if heat is an issue
than larger heatsinks or fans are the solution.
Keep in mind speculation is not measurements.? For 50W out?
your input DC at 20V has to be in the range of 70 to 90W
assuming 70 to 50% efficiency.? The difference between output
power and input power is resulting in heat.? Power amplifiers?
above the milliwatt range are all concerned with heat and
managing it.
I have used the same heatsinks for the QRPLabs 10W SSB amp?
at higher voltages and power there is a lot of heatsink there.? Running
bias in the 100Ma per device range is fairly trivial at 4W.? Even at 250ma
we are at under 10W.? ? Considering at 50W out the likely current? is
3.6A at 20V and converting 30% of that to heat for classC and much
Less (typical is 55%, average) for class AB1.
For SSB running to 50W peak the average is likely closer to 20W
and the heat load is maybe near 20W average as well assuming
50% efficient and that would be low.? So heat should not be an issue
with supplied heatsinks and reasonable airflow (no sealed chassis)
and not over driven.
It should be noted that for SSB the peak power is around 50W the
average will be lower and should be to avoid splatter from clipping.
That means the SSB drive power should be lower than CW.
Allison
---------------------------------
No direct email, it goes to bit bucket due spam
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Re: ?BITX & QRP labs 50W PA
Allison, great information!? ?That sheds a great deal of light on the subject, thanks!
On Tue, Dec 17, 2019 at 11:26 AM ajparent1/kb1gmx < kb1gmx@...> wrote: Since I run an EBY amp since 2006 you must have mis-read.? In the files section
I've even posted his articles back around 2010 and copied to this iteration years
ago. Still there.
The ubitx is not run that low, spec is 100ma per.?
The irf510 like all fets has a considerable hook at low gate to source voltages.
If the gate voltage is platted against the drian current the linear window is above
100ma and below saturation or about 4A.? Below that in the low end under 100ma?
drain current he gate voltage is not linear at all from start of conduction to the?
100ma range and? that makes for very non linear near cross over.? Class AB1
is more like 80-150ma but it is very toplology dependent.
His (WA2EBY) minimum was 50 ma per device for CW and testing put it higher
near 100ma per device for SSB to get a decent IMD at 28V.? I find mine
comfortable at 125 ma per device and the two tone testing is good enough at
about -28dbc.? However that design has the features needed for linear operation
including independent device bias,??current sourcing transformer for the drains
and large ferrite for the output transformer.
At 100ma per you only talking a standing power of 2.8W at 28V per device,
if that gets warm the heatsink is inadequate.?
So saying a specific current, especially low under 100ma, is inadequate
for linear use without testing questionable.? Especially for an amp designed
for class C use.? I do not say it cant be linear but at low bias its highly unlikely.
I have one on the way so testing will happen.
Allison
--
---------------------------------
No direct email, it goes to bit bucket due spam
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Re: ?BITX & QRP labs 50W PA
Since I run an EBY amp since 2006 you must have mis-read.? In the files section
I've even posted his articles back around 2010 and copied to this iteration years
ago. Still there.
The ubitx is not run that low, spec is 100ma per.?
The irf510 like all fets has a considerable hook at low gate to source voltages.
If the gate voltage is platted against the drian current the linear window is above
100ma and below saturation or about 4A.? Below that in the low end under 100ma?
drain current he gate voltage is not linear at all from start of conduction to the?
100ma range and? that makes for very non linear near cross over.? Class AB1
is more like 80-150ma but it is very toplology dependent.
His (WA2EBY) minimum was 50 ma per device for CW and testing put it higher
near 100ma per device for SSB to get a decent IMD at 28V.? I find mine
comfortable at 125 ma per device and the two tone testing is good enough at
about -28dbc.? However that design has the features needed for linear operation
including independent device bias,??current sourcing transformer for the drains
and large ferrite for the output transformer.
At 100ma per you only talking a standing power of 2.8W at 28V per device,
if that gets warm the heatsink is inadequate.?
So saying a specific current, especially low under 100ma, is inadequate
for linear use without testing questionable.? Especially for an amp designed
for class C use.? I do not say it cant be linear but at low bias its highly unlikely.
I have one on the way so testing will happen.
Allison
--
---------------------------------
No direct email, it goes to bit bucket due spam
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Re: ?BITX & QRP labs 50W PA
Hi,
I think linearity will depend on a lot of things, most importantly supplied voltage and bias current (and likely input signal level as well).?? I would think it would also depend on the design of the amplifier and not only on what output device it uses.
In WA2EBY's article, he doesn't show or talk about any linearity measurements that he might have made, only that "No indications of instability, CW key clicks or distortion on SSB have been reported." which is not really a reliable test.
So I would either say as Jerry does and have a way to measure IMD distortion, or go with what the designer recommends.? For SSB, unless you are really long-winded, is it probably is OK to have higher idle currents; 250mA at 20V is only an idle of 5W so not so bad if the heatsink is good for intermittant 50W.? Regardless, it would be nice to see some test results showing IMD versus idle current so it could be set it as low as it can.?
73,
Mark.
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Re: Templates for China EF01 Electronic Plastic Shell Project Case for a BITX40
Thingiverse has quite a few front panels for this as well available as models that can be 3d printed. they work quite well
as an example but there are quite a few!
On Tue, Dec 17, 2019 at 9:27 AM < pluto@...> wrote: I?I bought this case (S06A):?
It is not a real bargain but it comes complete with useful accessories
Cheers,
Diego I8TIF
--
Tim Keller - KE2GKB
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Re: [GCBG] HF Coupon for case
Yeah, I didn't notice the fine print as I was buying a gift for my son. Sorry about that.
Jack, W8TEE
On Tuesday, December 17, 2019, 9:46:59 AM EST, <kd8vrx@...> wrote:
$5 is a steal but the fine prints says "only available with qualifying $49.99 minimum purchase".? Most of us can find a way to spend that much, there's always something you can use/need.? I have a few of these cases and they are very good, the MFJ Analyser will also fit in one of those, which is perfect for field day.
Jocelyn
KD8VRX
-- Jack, W8TEE
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Re: Templates for China EF01 Electronic Plastic Shell Project Case for a BITX40
I?I bought this case (S06A):?
It is not a real bargain but it comes complete with useful accessories
Cheers,
Diego I8TIF
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Re: Templates for China EF01 Electronic Plastic Shell Project Case for a BITX40
You could mock up front and rear panels on stiff card, easy to make changes and when you are happy use as your front and rear templates.
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Re: ?BITX & QRP labs 50W PA
Most of the the VU2s use a laptop smps with a bit of filtering to give nearly 20 watts out. I don't think there is a need of another amp since the devices are the same
de vu2pep?
On Tuesday, December 17, 2019, 05:28:23 PM GMT+5:30, John AE5X <ae5x@...> wrote:
At $300 the HR-50 supports the uBITX on all bands and modes. And it does not require a PTT In signal since it has a carrier-operated relay:
John AE5X
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Makes me think of the Led Zepplin song.
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Ken:
I didn't notice that as I used it when I bought my son a Christmas gift. Still, it's a pretty good deal.
Jack, W8TEE
On Tuesday, December 17, 2019, 9:12:30 AM EST, Ken Hansen <ken@...> wrote:
That $5 price is after an additional $49.95 purchase. I agree, it is a great little case - I use one to hold a DMR HT, Pi-Star hotspot, USB battery pack for both, and a charger as a mini DMR go-box 'solution' - just add wifi and you're one the air' (so to speak). Ken, N2VIP
On Dec 17, 2019, at 08:05, Jack, W8TEE via Groups.Io <jjpurdum@...> wrote:
? All:
Harbor Freight has this coupon:
<hfCoupon.jpg>
for the small Apache case. It's regular price is $15 and often on sale for $10, but $5 is the cheapest I've seen it. I put Diz's 5 W in one:
and it worked out well. I put all the connectors on the top panel so it remains watertight and still has room for paddles, earbuds, and antenna.
Jack, W8TEE
--
Jack, W8TEE
<hfCoupon.jpg> <FigureJ(Small).jpg> <hfCoupon.jpg>
--
Jack, W8TEE
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That $5 price is after an additional $49.95 purchase. I agree, it is a great little case - I use one to hold a DMR HT, Pi-Star hotspot, USB battery pack for both, and a charger as a mini DMR go-box 'solution' - just add wifi and you're one the air' (so to speak). Ken, N2VIP
toggle quoted message
Show quoted text
On Dec 17, 2019, at 08:05, Jack, W8TEE via Groups.Io <jjpurdum@...> wrote:
? All:
Harbor Freight has this coupon:
<hfCoupon.jpg>
for the small Apache case. It's regular price is $15 and often on sale for $10, but $5 is the cheapest I've seen it. I put Diz's 5 W in one:
and it worked out well. I put all the connectors on the top panel so it remains watertight and still has room for paddles, earbuds, and antenna.
Jack, W8TEE
-- Jack, W8TEE
<hfCoupon.jpg> <FigureJ(Small).jpg> <hfCoupon.jpg>
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All:
Harbor Freight has this coupon:
for the small Apache case. It's regular price is $15 and often on sale for $10, but $5 is the cheapest I've seen it. I put Diz's 5 W in one:
and it worked out well. I put all the connectors on the top panel so it remains watertight and still has room for paddles, earbuds, and antenna.
Jack, W8TEE
-- Jack, W8TEE
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Alex Netherton
