Re: uBITX V6 Specifications.
My uBITX older version works well on a 3A battery source, regulated 12V. If you want some extra room, you might want a 3.5 or 4A capability.?
Earl Cox? KB5UEW? Reply or E-mail me at:? kb5uew@...
On Tuesday, May 4, 2021, 02:35:31 PM MDT, Robert AG6LK <amrmedic@...> wrote:
Hi All,
What's the transmit current? What do you think about 2.5ah? What do you think the minimum power supply should be 3a, 4a?
73,
.
Robert, AG6LK
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Re: uBITX V6 Specifications.
Found some PL906090 6AH 3.7V li batteries, each weighing 3.5oz. #.5*3=10.5oz = 12V@6Ah. 10.5oz*4 = 42oz = 24AH if I did that right. 42oz/16=2.625 lbs. + case. On testing these, they seem to be close to the rated capacity.
Earl Cox? KB5UEW? Reply or E-mail me at:? kb5uew@...
On Tuesday, May 4, 2021, 09:27:57 AM MDT, Max via groups.io <kg4pid@...> wrote:
My 12v 20Ah LiFePo4 battery weighs about 7 lbs. What have you found that would weigh half of that?
Max KG4PID
On Tuesday, May 4, 2021, 09:52:05 AM CDT, Earl Cox via groups.io <kb5uew@...> wrote:
SSB, CW will be most of the time. I have not dived into digital yet. I am looking at 12V, 24AH. I can achieve that in a case of about 5 1/4" X 4" X 3 1/4" weighing a little over 3 lbs.
Earl Cox? KB5UEW? Reply or E-mail me at:? kb5uew@...
On Tuesday, May 4, 2021, 08:39:25 AM MDT, Evan Hand <elhandjr@...> wrote:
Earl,
I will verify when I get to my rig.? Until then, what mode will you be using?? SSB voice, vs CW, vs digital modes makes a difference.? If digital then I would estimate that you need 720mah and CW at slightly less than that.? SSB would have even lower requirements, most likely 50% of digital mode.? That means for 48 hours of continuous operation you would need a 34.5ah battery for digital and 18ah for SSB.? That would be a large battery.? Maybe look into a solar panel as a part of the power scheme.
Please check my math before you commit to a battery.
73
Evan
AC9TU
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Re: uBITX V6 Specifications.
Hi All,
Thanks for the information everyone.?
That¡¯s about what I figured a 4a power supply would be the safest, with some room for improvements, like a 5¡± display with it's own power supply. Actually I¡¯m just starting to build a v6 with a ?Universal Case for a 5¡± Nextion from Sunil (Nice guy) with Inkits, amateurradiokits.in. It¡¯ts a lot of case and extras for the money. It's just too bad DHL shipping cost about 50% of what you pay for the case.
I have a couple of more questions for the group, if you don¡¯t mind. I¡¯m thinking on using a step down Buck converter module to power the 5 volts needed for the 5¡± Nextion. I here that if you use a larger display you should have its own power supply so you don't do damage to the display, in case the voltage drops too low. Do you think that the Buck converter would be a good choice to power it??How much extra current do you the 5¡± display would use compared to the stock 2.8¡± display. Should I get a larger power supply than a 4a? I¡¯m also thinking of placing a ATU 100 in the case also. I can't imagine though that it would use more than 600 - 700ma. So should I go with more like a 5a power supply.
Last question, what do you think the best switching, hopefully, ¡°low noise¡± power supply is out there?
I apologize Earl, I didn't mean to but-in and take up your whole page. I hope you don't mind. Again Earl, I apologize.
73,
Robert Guentz
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Re: technical question about filter capacitors
just one example ... if you search for storage box you will find
a few dozen ..
dg9bfc sigi
Am 04.05.2021 um 16:27 schrieb Gerard:
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The small jars remind me of a bacteria farm. LOL.
Each one has its own method, my SMD being in strips, I keep them in plastic bags.
It¡¯s not bad and spring prices here:
cdt
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Re: technical question about filter capacitors
To measure really small capacitors, say 20 pF or less, the AADE unit (no longer available) or its equivalent, the LC-100A or LC-200 devices from China work well. Also, A caveat: They pretty much all used to be good, then came the clones.Those testers use Atmega628 microcontrollers or equivalent. I bought my LC-100A several years ago on eBay for less than $15. I checked it out with several 1% caps from Mouser, and it is accurate. Chuck Adams, K7QO posted the results of his measurements on the for qrp-tec Yahoo group, and his results are similar to mine. These LC testers, including AADE, test at high-kilohertz range.? Phil Rice, VK3BHR developed a homebrew AADE type LC tester that uses a PIC 16F84 or 16F628 several years ago, and it has a following at:
https://sites.google.com/site/vk3bhr/home/lcm1
Some say you can't get a proper measurement of the cap unless you measure at the frequency that you are going to be using the capacitor at, in the MHz range. While that sounds good, what to make of the schematic that says only "120 pF" instead of "120 pF at 7.200 MHz" ? I have not found 1% monolithic or C0G ceramic from Mouser more or less than 1% off. The LC tester devices mentioned include zeroing the leads before making the measurement. With SMD capacitors I use the type of device in post #88096 by Arv Evans. I have measured my collection of variable caps with it, marking the ranges on them.
These LC testers should not be confused with these:
That project has over nearly 7,000 posts dating back to 2013 to date, and has a *very* large following. To understand the scope and latest info, go to the end of the blog, and study the latest 10 pages of posts. The project is open source, with two current developers.
Ted, KX4OM
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Re: uBITX V6 Specifications.
Just as a point of interest: I have a Xiegu X1M Platinum Pro.? It
uses about 1250-1300 ma. on transmit, and this is a 5 watt CW
value.? Figure the uBITX would likely be in about the same
ballpark.
Gerry
Sent by the Thunderbird
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On 2021-05-04 3:33 p.m., Robert AG6LK wrote:
Hi All,
What's the transmit current? What do you think about 2.5ah? What
do you think the minimum power supply should be 3a, 4a?
73,
.
Robert, AG6LK
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Re: uBITX V6 Specifications.
Robert,
I have not seen my v6 go over 2.5amps on CW transmit.? I have not checked with digital modes.? 3amp power supply or better would be my recommendation.
73
Evan
AC9TU
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Re: technical question about filter capacitors
A nanovna for $40?can measure the impedance of a cap
over a range of frequencies from 50khz to 1ghz.
At some point the cap is self-resonant, and beyond that a cap starts
looking like an inductor due to the length of the leads into the plates
and perhaps the inductance of the plates themselves.
Inductors do the vice-versa, turning into caps at high frequencies
due to any capacitance between windings.
Jerry, KE7ER
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On Tue, May 4, 2021 at 01:41 PM, Jerry Gaffke wrote:
How small is really small?
That Nano clone trick works with caps between 1pF and 1000uF.
? ?/g/BITX20/message/52471
Way better than the capacitance meter in my $20 DVM.
Jerry, KE7ER
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Re: Split power for PA on uBITX v6
While I understand the rationale for the V6 board design, ease of assembly, the board design negates one of the best points of the BITX radios, the ability to easily try new things.? I REALLY wish the old V5 design was still being offered!
As far as splitting the PA power out, it looks like a little butchering is the only way to accomplish that.
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Re: technical question about filter capacitors
How small is really small? That Nano clone trick works with caps between 1pF and 1000uF. ? ? /g/BITX20/message/52471Way better than the capacitance meter in my $20 DVM. Jerry, KE7ER
On Tue, May 4, 2021 at 01:24 PM, jerry@... wrote:
To measure really small caps, I've used a resonant circuit.
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Re: uBITX V6 Specifications.
Hi All,
What's the transmit current? What do you think about 2.5ah? What do you think the minimum power supply should be 3a, 4a?
73,
.
Robert, AG6LK
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Re: technical question about filter capacitors
To measure really small caps, I've used a resonant circuit. You make up a coil of appropriate value and put it in series or parallel with the cap in question. Then
hook a scope and an oscillator. If you use a parallel resonant circuit, you need to put a series resistor so the
resonant tank has something to short out.
Once upon a time, I made a little jig to help me with such
endeavors. Of course, it only works with parts that have leads.
- Jerry KF6VB
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On 2021-05-04 12:28, Jerry Gaffke via groups.io wrote: I watched that 18 minute video so you don't have to.
Here's my review: He has a lab full of really nice gear.
His technique is to drive a 1v square wave from a 50 ohm source into
the cap,
measure the rise time t to 63.2%, or 632mV with a scope.
And calculate the capacitance from C = t/50ohms (C in Farads, t in
seconds).
Google for "RC time constant" if this is puzzling.
The caps he measured were all in the neighborhood of 1uF.
For some reason, he assumes one end of any cap is connected to the
ground plane.
He assumes there is nothing in parallel (except maybe an obvious row
of similar parts) with that cap.
Looking over the uBitx schematic, I see very few caps where this
technique would work.
My method for measuring caps (or resistors) in circuit:
Take it out of the circuit and measure it.
With reasonably long traces, some really fast test gear, and careful
technique,
you might be able to measure some low value individual components by
looking at
the reflection from that square wave before reflections from other
parts start coming in.
Good luck with that!
Jerry, KE7ER
On Mon, May 3, 2021 at 01:45 AM, Gerard wrote:
I put a video on it to find the value without desolding, but you
have to be equipped
And not sure his method work on very low capacitors.
(18) How to test or measure SMD capacitors on the PCB / on circuit
measurement free electronics training - YouTube [1] Links:
------
[1]
[2] /g/BITX20/message/88121
[3] /mt/82546658/243852
[4] /g/BITX20/post
[5] /g/BITX20/editsub/243852
[6] /g/BITX20/leave/10189903/243852/952924773/xyzzy
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Re: technical question about filter capacitors
I watched that 18 minute video so you don't have to.
Here's my review:? ?? He has a lab full of really nice gear.
His technique is to drive a 1v square wave from a 50 ohm source into the cap,
measure the rise time t to 63.2%, or 632mV with a scope.
And calculate the capacitance from C = t/50ohms? (C in Farads, t in seconds).
Google for "RC time constant" if this is puzzling.
The caps he measured were all in the neighborhood of 1uF.
For some reason, he assumes one end of any cap is connected to the ground plane.
He assumes there is nothing in parallel (except maybe an obvious row of similar parts) with that cap.
Looking over the uBitx schematic, I see very few caps where this technique would work.
My method for measuring caps (or resistors) in circuit:
? Take it out of the circuit and measure it.
With reasonably long traces, some really fast test gear, and careful technique,
you might be able to measure some low value individual components by looking at
the reflection from that square wave before reflections from other parts start coming in.
Good luck with that!
Jerry, KE7ER
On Mon, May 3, 2021 at 01:45 AM, Gerard wrote:
I put a video on it to find the value without desolding, but you have to be equipped
And not sure his method work on very low capacitors.
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Re: technical question about filter capacitors
The SMD parts I get from Digi-Key and Mouser come in small plastic labeled bags. I just leave them in the bags and line up the bags in storage boxes. The labels have the value, working voltage and part number.
?
I save the bags and reuse them for parts from other vendors. I write the new value on the label.
?
The bags are lined up by value.
?
Mike N2MS
?
On 05/04/2021 10:03 AM Jack, W8TEE via groups.io <jjpurdum@...> wrote:
?
?
?
Good idea. I typically take one jar and mount all of the caps/resistors of that value on the board at one time, then move on to the next value. As a result, I never have more than one jar open at a time. Also, they hang on the wall on a board and I wouldn't be able to read their values if the jar is labeled. However, if you store them on a shelf, or have a way to store them "laying on their side", your approach is more bullet proof.
?
Jack, W8TEE
?
On Tuesday, May 4, 2021, 7:52:16 AM EDT, Bill Cromwell <wrcromwell@...> wrote:
?
?
Hello Jack,
The only trouble with those labels is putting them on the
interchangeable lid. If it is possible for them to be swapped it *will*
happen. You are welcome to ask me how I know this. I recommend placing
the label on the jar.
73,
Bill KU8H
bark less - wag more
?
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Re: technical question about filter capacitors
Gerard:
I would like to put a module that decodes the MORSE directly on a PC
This is very hard to do well. It's not too hard to get one to decode the W1AW code practice sessions because those are perfectly-generated characters. However, throw in a person's "fist" and things get considerably tougher. No individual can consistently maintain the 1-3-7 spacing that is required for good code parsing. There are a number of good ones out there like Hans' QCX and code by Bud Churchward, but still will hiccup along the way.
Jack, W8TEE
On Tuesday, May 4, 2021, 2:14:34 PM EDT, Gerard <kabupos@...> wrote:
Thank you Jerry for your response.
The basic question was what type of capacitors were on the filters at the output of the UBITX power amplifier.
The answer is clear, and given by the creator, it is SMD 100v.
I asked this question because on antenna tuner mounts we had 1000V capacitors.
Secondly, with regard to measurement, it is clear that testers have difficulty reading a value below 25PF.
In terms of the marking, clearly there is no marking.
I have SBM bands and the value is shown behind it.
You have to be careful, and I¡¯ve already been fooled on reading.
100 is not 100PF, but 10PF and 101 is 100PF.
Then concerning the storage, each to its own method.
I asked those questions, because in fact?I¡¯m back to electronics and my passion has always been radio.
I will still make changes on my Cocorico Ubitx and keep you informed, but of course, there are other things to do in the meantime.
Like here, I have provided modular SSB filters
Afterwards, and just out of curiosity, I would like to put a module that decodes the MORSE directly on a PC and made the reverse. But one thing at a time.
Cdt
-- Jack, W8TEE
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Re: technical question about filter capacitors
Thank you Jerry for your response.
The basic question was what type of capacitors were on the filters at the output of the UBITX power amplifier.
The answer is clear, and given by the creator, it is SMD 100v.
I asked this question because on antenna tuner mounts we had 1000V capacitors.
Secondly, with regard to measurement, it is clear that testers have difficulty reading a value below 25PF.
In terms of the marking, clearly there is no marking.
I have SBM bands and the value is shown behind it.
You have to be careful, and I¡¯ve already been fooled on reading.
100 is not 100PF, but 10PF and 101 is 100PF.
Then concerning the storage, each to its own method.
I asked those questions, because in fact?I¡¯m back to electronics and my passion has always been radio.
I will still make changes on my Cocorico Ubitx and keep you informed, but of course, there are other things to do in the meantime.
Like here, I have provided modular SSB filters
Afterwards, and just out of curiosity, I would like to put a module that decodes the MORSE directly on a PC and made the reverse. But one thing at a time.
Cdt
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Re: technical question about filter capacitors
If we are talking about storage, one that I use is coin envelopes and VCR tape boxes, that I have glued dividers in the width of the coin envelopes.? I expect VCR tape boxes are pretty rare? now days, shoe boxes might be a good? alternate.? I keep resistors, IC's, and any small parts that I want to keep on hand.? Hope I am not to far off topic. john kg9dk?
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Re: technical question about filter capacitors
Hi,
I just string my SMD parts, by type and value, on a wire like on a fish stringer (threading through the last hole in the strip) and hang them on my workbench peg board.?? Takes up hardly any room and is very fast to find and take out parts from the strip.
73,? Mark
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Re: technical question about filter capacitors
If you have a spare Nano clone for your Bitx40 or uBitx,? then you have all you need to build a capacitance meter: /g/BITX20/message/52471You can use the Arduino IDE serial monitor on your computer to read values from the Nano, or could be extravagant and blow an extra $2 on a 16x2 LCD. A couple probes on short wires works fine, you don't really need the tweezer thingies. On parts of only a few pF, hold the probes above the part first to get a zero reading, then subtract that value when probing the part. Resistors of size 0603 and larger seem to always be marked and quite readable under magnification.? For resistors of size?0402 and smaller they don't bother, though looks to me like there's plenty of room on an 0402. Surface mount ceramic caps are seldom marked, even when they are quite large. Perhaps the different finish on them would mean an extra processing step to print a value on it, and an additional $0.001 per part. Perhaps it's just because nobody else ever has, so customers don't expect it. Cap markings would be most welcome, just in case somebody from?Kemet/Murata/KOA/AVX/CTS/...? happens to be listening in. When building I do one part type at at time, dumping out and carefully counting enough? of that part to populate the board.? ?If that leaves an empty spot on the board, I know I put one in the wrong place.? I measure at least one of them, even if they are marked. The manufacturer very seldom goofs up on the value, but I goof up on reading it often enough. Jerry, KE7ER
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Gerard
John KG9DK
