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Different Encoder

 

I have been looking into using a different encoder, I have an optical 400ppr which is very smooth (fresh from China) looks to be good quality but is close to 2 inches in diameter. I ran across a neat looking capacitive ?unit that can be set from 48 ppr to over 2000 ppr ?which looked interesting to me. They say they have a longer life than the magnetic or optical. The one I was looking at was made by CUI ?and the number of it is AMT103-V. I ordered one from Mouser. The shaft goes through it which I close to what I wanted . I plan on using a bearing on each side of the encoder with a flywheel (metal disc) on the back side which should have a good free spinning motion. Speed is going to depend on how fast the arduino can read it so this is where the adjustable ppr setting would come in handy.?
--
Allen ?Merrell
Re: Power supply fuses

 

I'd put that fuse in the +12 line first.?
Easy to imagine supply ground having an alternate path through house wiring and RF ground rods,
vehicle sheet metal, etc.? I believe Allison once said she puts fuses on both +12v and ground,
which is more than I usually see.

Splitting it into two portions, fusing most of the rig at 0.5 Amps and the IRF510's at 3 Amps,
means you don't need a smoke inducing event within the main part of the uBitx to blow the 0.5A fuse.


On Thu, Jun 7, 2018 at 02:26 pm, <entilleser@...> wrote:
In the event that the power supply voltage is reversed, the reverse polarity protection diode, as suggested by HFSignals, will short circuit the power supply.? If the power supply has a small enough fuse, the short circuit will cause that fuse to blow, which will disconnect the power supply, therefore protecting your uBitx.? However, if the fuse in the power supply is too large, the diode may burn out before the fuse does, resulting in the reversed polarity being applied to your radio, causing damage.? It seems to me the simplest solution is to put a 2A fuse in the ground line before the diode.? If the polarity is reversed, the diode will still short circuit the power supply, which will result in blowing the 2A fuse (and therefore disconnecting the power supply), rather than burning out the diode.? Then you don't have to rely on an unknown fuse in the power supply itself.
Re: RF power chain mods and improvements..

 

I've printed this out. Something to do on a rainy day maybe?

Thanks,

tim ab0wr

On Thu, 07 Jun 2018 10:33:24 -0700
"Jerry Gaffke via Groups.Io" <jgaffke@...> wrote:

Here's an outline of how to get dangerous with LTSpice:

Download the free LTSpice from Linear Tech:
? ??
It primarily targets the various MSoftWindows operating systems.
They also have a version out now for Mac OS-X.
Will run under linux with Wine.

Also download this
file:??/g/BITX20/files/KE7ER/ubitx_pa.asc

Kick off LTSpice.
Click File, then Open, browse for that ubitx_pa.asc file you just
downloaded. Should display a schematic of Q90 on out through the
finals for the uBitx.

Click the RunningMan menu icon (5 over from the left edge) to run the
simulation. It should open a second window to show waveforms, but the
window will be empty. Click on nodes in the schematic to see the
voltage waveform at that point. Double clicking will erase all other
waveforms and just show the last one selected. Click where wires
enter into part symbols to see currents there.

Edit part values by clicking on that value.
Edit wires by using the Scissors icon to cut away wires, then using
the Pencil icon to add new wires.? (You first have to click somewhere
in the schematic to select that window.) You can add grounds, caps,
coils, resistors and diodes by clicking on their icon in the menu
bar. Click the AND-GATE icon to explore the various other parts
available to you.

Someday, click the Help menu item, browse the destructions.

LTSpice is an incredible gift from LinearTech to the electronics
hobbyist and professional engineer. It has a full catalog of the
various LinearTech products and complete demo circuit simulation
models for each. Fortunately, it is also a first rate generic analog
simulator with an easy to use interface.

Jerry, KE7ER

On Thu, Jun 7, 2018 at 09:37 am, Jerry Gaffke wrote:


I'm not one that takes easily to new tools,?
but found LT-Spice easy to get started with.
Changes can be hacked in and checked faster than it takes for my
soldering iron to heat up.
You can easily instrument voltage, current, power dissipaton, and
much more.
It's worth a couple hours of fiddling with to get started.
I'm no expert, but let me know if you get hung up on those first
steps.
Re: RF power chain mods and improvements..

 

Jerry,

I've prototyped things for 55 years. It's why I like Surfboards so
much.

I might try LT-Spice someday again if I ever get any spare time.

My ubitx is built in a U-type case, a U bottom matched with a U top.
Pain in the butt to get to the bottom!

Right now I'm trying to figure out why this mmic amp is giving me 25db
gain instead of 12db. Don't know if I am measuring wrong or the
datasheet is wrong below 500mhz.

It's so doggone simple its hard to believe I am measuring wrong!

tim ab0wr

On Thu, 07 Jun 2018 09:37:57 -0700
"Jerry Gaffke via Groups.Io" <jgaffke@...> wrote:

Tim,

I'm not one that takes easily to new tools,?
but found LT-Spice easy to get started with.
Changes can be hacked in and checked faster than it takes for my
soldering iron to heat up. You can easily instrument voltage,
current, power dissipaton, and much more. It's worth a couple hours
of fiddling with to get started. I'm no expert, but let me know if
you get hung up on those first steps.

My uBitx is easily flipped over, I don't mind working on the bottom.
The (mostly) solid ground plane (mostly) ensures my new stuff doesn't
see the old stuff. And vice-versa.

Jerry, KE7ER

On Thu, Jun 7, 2018 at 09:13 am, Tim Gorman wrote:


Jerry,

One of the reasons I want to put it before Q90 is to make it easy to
access and test.

If you'll remember I was the first person on here to show spectrum
analyzer screen shots showing how the 3rd order IMD and carrier
suppression is marginal. I don't plan on doing anything less with
this amp in the chain. If Q90 distorts it should show up in 3rd
order IMD results.

I'm not much on LTSpice and that genre of software. I tried using it
once but just too many demands on my time to learn how to use it.
Easier to just measure actual results!
Re: CW transmit bandwidth #ubitxcw #ubitx

 

I agree with Jerry that it sounds like maybe the CW keying is too sharp. ?That would explain a wider than expected bandwidth.?

I haven't really looked at the uBITX schematic in any detail so I can't?comment on what is being done with regards to CW Waveform shaping.
I just unpacked my uBITX V3 board and I am?starting to look at initial wire up. Once it is working I can do a similar investigation to what I did for the Bitx40.

Cheers

Michael VE3WMB?
Re: Power supply fuses

 

In the event that the power supply voltage is reversed, the reverse polarity protection diode, as suggested by HFSignals, will short circuit the power supply.? If the power supply has a small enough fuse, the short circuit will cause that fuse to blow, which will disconnect the power supply, therefore protecting your uBitx.? However, if the fuse in the power supply is too large, the diode may burn out before the fuse does, resulting in the reversed polarity being applied to your radio, causing damage.? It seems to me the simplest solution is to put a 2A fuse in the ground line before the diode.? If the polarity is reversed, the diode will still short circuit the power supply, which will result in blowing the 2A fuse (and therefore disconnecting the power supply), rather than burning out the diode.? Then you don't have to rely on an unknown fuse in the power supply itself.
Re: RF power chain mods and improvements..

 

As Allison says, the simulation and the real world won't always agree.
For example, like most spice simulators, it simulates the normally used region and doesn't bother with bounds checking.
So the 2n3904's in your simulation will work quite well with 1kV of Vce and 100A of Ic, if that's what you ask of them.

But in most cases, it's very helpful, allows you to see inside the circuit and figure out what's going on
without filling the room with smoke.? And usually accurate enough.

An RF power amp has a lot of little things that become significant, and can derail a simulation.
Perhaps an extra half inch of trace from ground to IRF510 source, for example.?
Or secondary capacitances in the parts not included in the model.
But still very useful, and generally more or less accurate.
LTSpice helped me figure out what was going on with all the magnetics in the uBitx.

Jerry


On Thu, Jun 7, 2018 at 12:51 pm, Gordon Gibby wrote:
Jerry, thank you so much for that running start on LT spice.
Re: uBitx Encoder information needed.

 

¿ªÔÆÌåÓý

Check message #45085 Jim - W0EB suggests the?part number in his message?from Digi-Key as being the exact replacement.
?
Rick KN4AIE


From: [email protected] [mailto:[email protected]] On Behalf Of tituskz1g@...
Sent: Thursday, June 07, 2018 5:02 PM
To: [email protected]
Subject: Re: [BITX20] uBitx Encoder information needed.

This encoder is similar to the Bourns PEC11L Series - 11 mm Low Profile Encoder.? Search for part number PEC11L-4115F-S0020-ND at DigiKey.com and click on the datasheet link for this product.? That document should give you information about the type of encoder.? I substituted an encoder with detents, but it did not work well.? The continuous rotation version that came with the kit works better.? If your encoder does not work, check solder connections and wiring.
--
Jon Titus, KZ1G
Herriman, UT USA

Re: Power supply fuses

 

All that PA-PWR goes to is the IRF510 drains.
There's an intrinsic diode from source to drain inside the IRF510 that will?
suck all the PA-PWR you care to give it if that supply line gets reversed.
Hopefully that will blow the 3A fuse.
If not, it will blow board traces and burn out the wire in the two RF chokes into the drains.
That damage is easily fixed, fixing a reverse voltage into the main 12v supply to the uBitx board is not.
Also, a? diode voltage drop into the main uBitx board is not an issue, even when running form a battery,
should do fine with 10 or 11 volts.

But a voltage drop feeding into the IRF510's will impact power out.?
So the fuse+shunt(intrinsic-irf510)diode scheme there is appropriate.

Jerry


On Thu, Jun 7, 2018 at 01:29 pm, <entilleser@...> wrote:
Well, if you're going to use two fuses, don't you need two diodes?
Re: uBitx Encoder information needed.

[email protected]
 

This encoder is similar to the Bourns PEC11L Series - 11 mm Low Profile Encoder.? Search for part number PEC11L-4115F-S0020-ND at DigiKey.com and click on the datasheet link for this product.? That document should give you information about the type of encoder.? I substituted an encoder with detents, but it did not work well.? The continuous rotation version that came with the kit works better.? If your encoder does not work, check solder connections and wiring.
--
Jon Titus, KZ1G
Herriman, UT USA
Re: Power supply fuses

 

Well, if you're going to use two fuses, don't you need two diodes?
Re: Power supply fuses

 

¿ªÔÆÌåÓý

Yes it should work fine,? might knock down the power a little. Would be better with 4 Schotky diodes.

They are going to HEAT!?? Probably over a watt for each of the 2 conducting diodes.? On battery it would be quite a waste of power.

Another detail,? chassis radio ground and 12V - battery input are not common. but separated by a diode?

I put an extra fuse inside the cabinet and just a 1N4007 to ground.? Ty wrapped extra fuse to some wiring.? I have never blow it.


73's

Mike


On 6/7/2018 12:53 PM, martin@... wrote:
I'm a newbie on here and just dipping my toe into the world of BITX's

If you're running the radio at 13.8v is there enough wriggle-room to cope with a 1.4v drop using a bridge rectifier?

Reverse polarity diodes are a blunt instrument when protecting equipment, you still have to find a replacement fuse if you're in the middle of nowhere.

I've used a bridge rectifier with the incoming 13.8v on the AC inputs and, whatever way round you connect it, you will always get the correct polarities on the +ve and -ve sides.

Martin

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...
Re: K5BCQ kits in BITX40 #bitx40

 

On Thu, Jun 7, 2018 at 01:01 pm, Joe wrote:
I was wondering if my 2 AGC boards were sent yet?
Kees has been updating his list.? Check here...
/g/BITX20/files/K5BCQ/K5BCQ%20AGC-Audio%20Kit%20OrdersALPH.ods
?
--

Re: Power supply fuses

 

I think that bridge rectifier is a bad idea.
Leaves your rig antenna port ground a diode drop away from your power supply ground.
A single schottky power diode in series with the supply coming into the main ubitx 12v supply line
would be a better idea, fused at 1/2 Amp.? If you hook up the power supply wrong, it just won't work.
So hook it up right.
I would feed PA-PWR separately, without a diode, and fuse it separately at 3 Amps or so.


On Thu, Jun 7, 2018 at 12:53 pm, Martin / G4VZO wrote:
I'm a newbie on here and just dipping my toe into the world of BITX's

If you're running the radio at 13.8v is there enough wriggle-room to cope with a 1.4v drop using a bridge rectifier?

Reverse polarity diodes are a blunt instrument when protecting equipment, you still have to find a replacement fuse if you're in the middle of nowhere.

I've used a bridge rectifier with the incoming 13.8v on the AC inputs and, whatever way round you connect it, you will always get the correct polarities on the +ve and -ve sides.

Martin
Re: Power supply fuses

 

Hello?

For my uBitx I use a Pacific Antenna kit named VoltTattler.
This montage has the following features:

- Simple through-hole construction
- Draws only around 1 mA in normal use.?
- Reverse polarity protection.
- Programmable Thresholds over a range of 4V to over 27V.
- Single button programming with audio feedback.
- Audible announces activation with power on and indicator with LED flashing green.
- Audibly announces by Morse code when input voltage exceeds user programmed thresholds.
- Flashing Red and Yellow LEDs indicate that a voltage limit has been exceeded.
- 3V digital status signals are available on a header
- Cheap protection for low voltage DC equipment.

interesting to avoid inversions of polarities and portable QRP, in battery operation to know the state of health of your batteries.

73 QRO from F1BFU

2018-06-07 21:10 GMT+02:00 entilleser via Groups.Io <entilleser@...>:

The "Fix reverse polarity" section on suggests a 0.5A fuse for the "rig" and 2A fuse for the "finals," but does not specify which wire is which.? The schematic says that the brown wire is "PA-PWR," but I am too much of a newphyte to be certain if this means the same as "finals" or "rig."


Re: K5BCQ kits in BITX40 #bitx40

 

I was wondering if my 2 AGC boards were sent yet?


Thanks
VE1BWV
joe Basque


On Wed, Jun 6, 2018, 11:18 AM Don, ND6T via Groups.Io <nd6t_6=[email protected]> wrote:
For those wondering if the K5BCQ AGC and ClickFix kits work with the BITX40, they do! The AGC works just as well as in the ¦ÌBITX and the ClickFix is, by far, the quietest modification that I have tried. The latter uses the PTT line for keying the receive preamp but that is all explained on the web site. No software changes are necessary unless you use the AGC board as an S meter source (which I recommend) and that is only to calibrate the display to accommodate the improved dynamic range. 73, Don

Re: Power supply fuses

[email protected]
 

I'm a newbie on here and just dipping my toe into the world of BITX's

If you're running the radio at 13.8v is there enough wriggle-room to cope with a 1.4v drop using a bridge rectifier?

Reverse polarity diodes are a blunt instrument when protecting equipment, you still have to find a replacement fuse if you're in the middle of nowhere.

I've used a bridge rectifier with the incoming 13.8v on the AC inputs and, whatever way round you connect it, you will always get the correct polarities on the +ve and -ve sides.

Martin
Re: RF power chain mods and improvements..

Gordon Gibby
 

¿ªÔÆÌåÓý

Jerry, thank you so much for that running start on LT spice.


On Jun 7, 2018, at 13:33, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

Here's an outline of how to get dangerous with LTSpice:

Download the free LTSpice from Linear Tech:
? ??
It primarily targets the various MSoftWindows operating systems.
They also have a version out now for Mac OS-X.
Will run under linux with Wine.

Also download this file:??

Kick off LTSpice.
Click File, then Open, browse for that ubitx_pa.asc file you just downloaded.
Should display a schematic of Q90 on out through the finals for the uBitx.

Click the RunningMan menu icon (5 over from the left edge) to run the simulation.
It should open a second window to show waveforms, but the window will be empty.
Click on nodes in the schematic to see the voltage waveform at that point.
Double clicking will erase all other waveforms and just show the last one selected.
Click where wires enter into part symbols to see currents there.

Edit part values by clicking on that value.
Edit wires by using the Scissors icon to cut away wires, then using the Pencil icon?
to add new wires.? (You first have to click somewhere in the schematic to select that window.)
You can add grounds, caps, coils, resistors and diodes by clicking on their icon in the menu bar.
Click the AND-GATE icon to explore the various other parts available to you.

Someday, click the Help menu item, browse the destructions.

LTSpice is an incredible gift from LinearTech to the electronics hobbyist and professional engineer.
It has a full catalog of the various LinearTech products and complete demo circuit simulation models for each.
Fortunately, it is also a first rate generic analog simulator with an easy to use interface.

Jerry, KE7ER


On Thu, Jun 7, 2018 at 09:37 am, Jerry Gaffke wrote:
I'm not one that takes easily to new tools,?
but found LT-Spice easy to get started with.
Changes can be hacked in and checked faster than it takes for my soldering iron to heat up.
You can easily instrument voltage, current, power dissipaton, and much more.
It's worth a couple hours of fiddling with to get started.
I'm no expert, but let me know if you get hung up on those first steps.
Re: Power supply fuses

 

¿ªÔÆÌåÓý

Speaking of Fusing and Over-Current protection.

I am experimenting with an LT6108 for a Real Fast over current limiter.

The circuit show is my 2 PCB, the LT part is fussy about getting reset.

I have it Latch Up, so you power down to reset.

The ap note says less than 5uS to shut down.

I got new PCBs coming.? The first go around I could not get LT to reset, it needs a 10uS pulse to get out of over

current condition.? I have a tiny (SOT 23-6) Pic programmed to do that.?

The PCB is about 1 3/4" x 1 1/8".? Should fit on back inside panel somewhere where power comes in on most chassis?


So 5uS seems like a really fast fuse to me?

73's

Mike, WA6ISP


On 6/7/2018 12:14 PM, ajparent1/KB1GMX wrote:
Finals, PA-PWR, output devices... the same.

The other is rest of rig.

PLEASE, put the fuses before the polarity protect diode.? Example Fuse, reverse polarity protection diode, radio.

Allison 

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...

Ilimit5ASch.pdf
Ilimit5ASch.pdf

Re: CW transmit bandwidth #ubitxcw #ubitx

 

So it's narrow when the key is down continuously, but a string of dots is 1khz wide?
That would be envelope shaping.? Has to do with how quickly the transmitter turns on and off when you key it.
Here's somebody who has looked at this:
? ??/g/BITX20/message/51423


On Thu, Jun 7, 2018 at 12:37 pm, K3OS wrote:
Just got a v3 board running today.? I was monitoring CW on my IC7300 and noticed that when transmitting, i.e., a string of dots or dashes, the bandwidth would widen to 1Khz then return to very narrow.? ?This occurred at a periodic rate if I held the dot or dash lever.? Internal keyer was used.? When sending text the same issue occurred but it was more difficult to spot.? Initial test was 40 meters, 12 watts out, but same results on 20, 8 watts out all into a dummy. 12.2VDC power supply.?

Any clues to why this happens and what can be done?

Gary K3OS
65361 - 65380 of 116645