Date   
Re: Case

Sam Tedesco
 

@Jack,  where did you find the tuning dial?

Re: ubitx v5 down: IRF510 heatsink very hot immediately after turning on the radio #ubitx-help #ubitx

Jerry Gaffke
 

Raj,

In what way is the FY6800 a bit flakey to operate?
I'm very curious, as am on the verge of buying one.

Lots of the FY6800 reviews mention it is better than the previous product
(I assume the FY6600) in that BNC ground is not driven with a DC offset from power plug ground.
Some complain that it is not yet ideal, that BNC ground should be independent of power plug ground.
Also a complaint or two that the internal switching power supply is a bit noisy on the FY6800.
Any comments?

Webpage for the FY6800 says 1mv resolution, not 0.1mv.
Do the FY6800 knobs really allow 0.1mv resolution in setting the pk-pk amplitude?

Webpage for the FY6600 also claims 1mv resolution:
  "Small signal is particularly good,FY6600 can outputs1mVPP small signal, amplitude resolution is 1mV, and can be 1mVpp, 10mVpp, 100mVpp, 1Vpp and other different step value, the maximum range is 1mVpp~20Vpp electrodeless stepless regulation."
With a 12 bit DAC and 20v pk-pk max, DAC step size is 20v/(2**12) = 20v/4096 = 4.88mv,
so must have some sort of VGA after the DAC if it can generate an accurate sine wave that is 1mv pk-pk.

Would be interesting to pop one open, see what frequency the reference oscillator is operating at.
Should be possible to modify it to switch between the internal reference and an external
GPS disciplined reference coming in through an SMA connector on the back.
Though for most of us, the claimed 1ppm stability as originally built is good enough.

Jerry, KE7ER


On Wed, Apr 17, 2019 at 12:00 AM, Raj vu2zap wrote:
Correction, the 6600 does go down to 1mV steps. The 6800 goes down to 0.1mV steps.
6800 is a bit flakey to operate.

Re: Case

Jim Sheldon
 

Another thing to consider with the blue cases from eBay etc., the panels ARE steel, but the major problem is they are mounted in a plastic frame.  There is no continuity between the front and back panels with each other and with the rest of the case.  I have used 2 of these cases and to eliminate or at least reduce ground loops in the circuitry, I had to use heavy braid from each panel via a solder lug under the corner standoff(s) of the mounted uBITX board.  If you don't do this, no telling what will or will not work on the radio due to missing grounds if something isn't quite connected right and you might have weird results when tuning, keying, talking with the microphone, etc.

This isn't something you can ignore unless you are extremely lucky.

Jim Sheldon, W0EB

------ Original Message ------
From: "Jack Brabham - KZ5A" <kz5a@...>
Sent: 4/17/2019 9:46:29 AM
Subject: Re: [BITX20] Case

I have one of those cases, the panels are all steel.  Really the whole case comes across as kind of "cheezy".   The cases  I am considering for my uBITX are a Cheval SA from Thailand or possibly the Circuit Specialist Instrument case.



The Cheval case is of better design and quality but you have cost and delays associated with shipping from Bangkok.  Also at the moment, they are closed for a National Holiday week.

The cases from https://amateurradiokits.in/ are pretty neat and are pre-punched and come with all the associated goodies.  The selections available vary from day to day,  so far they haven't had the "one" I liked best available.  I think these are an excellent bargain considering the goodies bag they came with.

73 Jack KZ5A

On 4/17/2019 5:30 AM, Lawrence Galea wrote:
Sorry about it folks
Probably the copy and paste didn't work and the previous link was posted instead.
Here is the correct link and I checked it 

https://www.banggood.com/250x190x110mm-Blue-Metal-Electronic-Enclosures-DIY-Power-Junction-Box-p-1067251.html?cur_warehouse=CN 

Wishing everyone a happy Easter



On Tue, Apr 16, 2019 at 11:23 PM Jim <Jscook@...> wrote:
That is a good recipe. Have to try it. Grin


On Apr 16, 2019, at 5:11 PM, Karl Heinz Kremer, K5KHK <khk@...> wrote:

Is this a new form of rick rolling? ;) Or are you suggesting we should leave our radios turned off on Easter and to enjoy a sweet treat instead? Or, did you post the wrong link?

--
Karl Heinz - K5KHK


Re: Case

Jack, W8TEE
 

Who sells the Cheval cases??

Jack, W8TEE

On Wednesday, April 17, 2019, 11:33:13 AM EDT, Fast hosts <beneagles71@...> wrote:


Great case got mine from Banggood for less than £20... going to fit my 7inch screen in a sloping mount on top of the lid.. 

On Wed, 17 Apr 2019 at 16:30, Jack Purdum via Groups.Io <jjpurdum=yahoo.com@groups.io> wrote:
It does look nice and not much more expensive. Thanks for bringing it to my attention!

Jack, W8TEE

On Wednesday, April 17, 2019, 11:27:51 AM EDT, Dave Dixon <wylyeguy2@...> wrote:


Jack,
      I am Dave G0AYD I have 3 of these boxes one houses my V3 and matching matching case housing my home brew  T match atu.I am currently building a digital swr/pwr meter so hope to house this in my other case.They are really good and sturdy the cost of post is nearly half the price of the box.but i brushed that aside once i had got the first one..BRILLIANT CASE, if you decide to buy one you wont be disappointed.Dave G0AYD FISTS 15892.CWOPS 2109 ROYAL SIGS 4209..GQRP 3309..

On Wed, 17 Apr 2019 at 15:46, Jack Brabham - KZ5A <kz5a@...> wrote:
I have one of those cases, the panels are all steel.  Really the whole case comes across as kind of "cheezy".   The cases  I am considering for my uBITX are a Cheval SA from Thailand or possibly the Circuit Specialist Instrument case.



The Cheval case is of better design and quality but you have cost and delays associated with shipping from Bangkok.  Also at the moment, they are closed for a National Holiday week.

The cases from https://amateurradiokits.in/ are pretty neat and are pre-punched and come with all the associated goodies.  The selections available vary from day to day,  so far they haven't had the "one" I liked best available.  I think these are an excellent bargain considering the goodies bag they came with.

73 Jack KZ5A

On 4/17/2019 5:30 AM, Lawrence Galea wrote:
Sorry about it folks
Probably the copy and paste didn't work and the previous link was posted instead.
Here is the correct link and I checked it 

https://www.banggood.com/250x190x110mm-Blue-Metal-Electronic-Enclosures-DIY-Power-Junction-Box-p-1067251.html?cur_warehouse=CN 

Wishing everyone a happy Easter



On Tue, Apr 16, 2019 at 11:23 PM Jim <Jscook@...> wrote:
That is a good recipe. Have to try it. Grin


On Apr 16, 2019, at 5:11 PM, Karl Heinz Kremer, K5KHK <khk@...> wrote:

Is this a new form of rick rolling? ;) Or are you suggesting we should leave our radios turned off on Easter and to enjoy a sweet treat instead? Or, did you post the wrong link?

--
Karl Heinz - K5KHK



--
Keith Baker - Communications technician (retired)

Re: Case

Jack, W8TEE
 

I'm pretty sure it was Dayton in the flea market...sorry.

Jack, W8TEE

On Wednesday, April 17, 2019, 11:43:56 AM EDT, Sam Tedesco <stedesco619@...> wrote:


@Jack,  where did you find the tuning dial?

Re: Case

Jack Brabham - KZ5A
 


I don't think they are quite back from Holiday yet, but they are taking orders on ebay today.

73 Jack KZ5A




On 4/17/2019 10:02 AM, Jack Purdum via Groups.Io wrote:
Who sells the Cheval cases??

Jack, W8TEE

On Wednesday, April 17, 2019, 11:33:13 AM EDT, Fast hosts <beneagles71@...> wrote:


Great case got mine from Banggood for less than £20... going to fit my 7inch screen in a sloping mount on top of the lid.. 

On Wed, 17 Apr 2019 at 16:30, Jack Purdum via Groups.Io <jjpurdum=yahoo.com@groups.io> wrote:
It does look nice and not much more expensive. Thanks for bringing it to my attention!

Jack, W8TEE

On Wednesday, April 17, 2019, 11:27:51 AM EDT, Dave Dixon <wylyeguy2@...> wrote:


Jack,
      I am Dave G0AYD I have 3 of these boxes one houses my V3 and matching matching case housing my home brew  T match atu.I am currently building a digital swr/pwr meter so hope to house this in my other case.They are really good and sturdy the cost of post is nearly half the price of the box.but i brushed that aside once i had got the first one..BRILLIANT CASE, if you decide to buy one you wont be disappointed.Dave G0AYD FISTS 15892.CWOPS 2109 ROYAL SIGS 4209..GQRP 3309..

On Wed, 17 Apr 2019 at 15:46, Jack Brabham - KZ5A <kz5a@...> wrote:
I have one of those cases, the panels are all steel.  Really the whole case comes across as kind of "cheezy".   The cases  I am considering for my uBITX are a Cheval SA from Thailand or possibly the Circuit Specialist Instrument case.



The Cheval case is of better design and quality but you have cost and delays associated with shipping from Bangkok.  Also at the moment, they are closed for a National Holiday week.

The cases from https://amateurradiokits.in/ are pretty neat and are pre-punched and come with all the associated goodies.  The selections available vary from day to day,  so far they haven't had the "one" I liked best available.  I think these are an excellent bargain considering the goodies bag they came with.

73 Jack KZ5A

On 4/17/2019 5:30 AM, Lawrence Galea wrote:
Sorry about it folks
Probably the copy and paste didn't work and the previous link was posted instead.
Here is the correct link and I checked it 

https://www.banggood.com/250x190x110mm-Blue-Metal-Electronic-Enclosures-DIY-Power-Junction-Box-p-1067251.html?cur_warehouse=CN 

Wishing everyone a happy Easter



On Tue, Apr 16, 2019 at 11:23 PM Jim <Jscook@...> wrote:
That is a good recipe. Have to try it. Grin


On Apr 16, 2019, at 5:11 PM, Karl Heinz Kremer, K5KHK <khk@...> wrote:

Is this a new form of rick rolling? ;) Or are you suggesting we should leave our radios turned off on Easter and to enjoy a sweet treat instead? Or, did you post the wrong link?

--
Karl Heinz - K5KHK



--
Keith Baker - Communications technician (retired)


Re: Homebrew li-ion battery pack into ubitx

Jerry Gaffke
 

Good info.
Can you recommend a "mini balance/charging plug"?

I'm not familiar with the devices currently out there, and the product descriptions don't really say what they do.
For example:
    https://www.amazon.com/Apex-RC-Products-Battery-Charger/dp/B01BQUVMZ4/ref=pd_lpo_vtph_21_bs_lp_tr_t_1?_encoding=UTF8&psc=1&refRID=Z1YSY98PBD680GE7Z8GH
Is this just a handy way of converting between the various connector styles, or does it include some sort of balance electronics?
If it has balance electronics, does this only work during charging, or will it work without a power source to balance the battery pack
by discharging those cells that show a higher voltage than the others?

I had assumed that a battery pack meant for a balance charger could not be charged without that special balance circuit in the charger.
But then, I guess the battery is just a stack of cells with wires into each junction between cells.
Though some include protection circuits, perhaps that protection from under/over-voltage and over-current is just a lump of electronics
at one end of the battery, looks like a short until an out-of-spec condition occurs, at which point it opens up like a switch or fuse?
Again, not obvious when reading the product descriptions.


Here's a few things I think I know, corrections welcome:

Since LiPo cells generally want to be charged to a max of 4.2v per cell, for a 3 cell battery we arrive at KE0GYC's figure of 3*4.2=12.6 volts.
Other lithium battery chemistries take a different maximum cell voltage, an LiPoFe4 battery wants a max of 3.6v per cell or it will be damaged.
Maximum charge rate in Amps is the Amp-Hour capacity for the battery times the specified C for charging.
Lipo batteries for model planes are designed to be able to charge quickly, let's assume a C of 20 and a 3 Amp-Hour capacity.
In this case, we could charge it at 20*3 = 60 Amps, and it would be full in about 1hour/20 = 3 minutes.
It is much safer to charge and discharge at lower rates, in this case charging at 3 Amps for an hour would be a better bet.
If charging at 500ma, it would take 3AmpHours/0.5Amps = 6 hours.

Actual times to achieve full charge will be greater than the above calculations show, as charging currents go down
as the battery gets close to full and efficiencies are not 100%.  Batteries don't need to be charged till absolutely full.
They will last longer if you don't try to completely fill them and keep charging currents down to something reasonable. 

Jerry, KE7ER
 


On Wed, Apr 17, 2019 at 06:30 AM, KE0GYC wrote:
ou can use any CC/CV charger set to the appropriate voltage and current settings.
I use a lot of the cheap dc-dc buck modules.
https://www.amazon.com/NOYITO-Adjustable-Regulator-Supply-Module/dp/B07G446KHJ/ref=mp_s_a_1_3?keywords=cc%2Fcv&qid=1555507232&s=gateway&sr=8-3

For the Turnigy pack, set the voltage to a hair under 12.6 and the current to 0.5A and connect to a DC source of 13.8V and it should charge just fine.  You can connect it directly to the discharge port.

As for balancing, I just plug one of these into the mini balance/charging plug every few charges.  It will drain the highest capacity cell slowly to balance the pack.  It doesn't need to be done every charge, but should be done periodically to maintain cell balance.

https://www.amazon.com/Turnigy-Battery-Display-Balancer-2S-6S/dp/B00USQXS1O/ref=mp_s_a_1_31?keywords=battery+balancer&qid=1555507626&s=gateway&sr=8-31

These will work with most any lipo battery pack, homebuilt or otherwise, as long as you have the right wire connections.

Re: Case

Rick Price
 

I installed the uBitx V3 in this case and later added the JackAl mod.  Everything fit nicely, all aluminum and easy to work with, very good acess, both top and bottom, front and back  panels are removeable.  A little pricey but nice construction.
 
Rick KN4AIE


From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Jack Brabham - KZ5A
Sent: Wednesday, April 17, 2019 12:20 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Case


I don't think they are quite back from Holiday yet, but they are taking orders on ebay today.

73 Jack KZ5A




On 4/17/2019 10:02 AM, Jack Purdum via Groups.Io wrote:
Who sells the Cheval cases??

Jack, W8TEE

On Wednesday, April 17, 2019, 11:33:13 AM EDT, Fast hosts <beneagles71@...> wrote:


Great case got mine from Banggood for less than £20... going to fit my 7inch screen in a sloping mount on top of the lid.. 

On Wed, 17 Apr 2019 at 16:30, Jack Purdum via Groups.Io <jjpurdum=yahoo.com@groups.io> wrote:
It does look nice and not much more expensive. Thanks for bringing it to my attention!

Jack, W8TEE

On Wednesday, April 17, 2019, 11:27:51 AM EDT, Dave Dixon <wylyeguy2@...> wrote:


Jack,
      I am Dave G0AYD I have 3 of these boxes one houses my V3 and matching matching case housing my home brew  T match atu.I am currently building a digital swr/pwr meter so hope to house this in my other case.They are really good and sturdy the cost of post is nearly half the price of the box.but i brushed that aside once i had got the first one..BRILLIANT CASE, if you decide to buy one you wont be disappointed.Dave G0AYD FISTS 15892.CWOPS 2109 ROYAL SIGS 4209..GQRP 3309..

On Wed, 17 Apr 2019 at 15:46, Jack Brabham - KZ5A <kz5a@...> wrote:
I have one of those cases, the panels are all steel.  Really the whole case comes across as kind of "cheezy".   The cases  I am considering for my uBITX are a Cheval SA from Thailand or possibly the Circuit Specialist Instrument case.



The Cheval case is of better design and quality but you have cost and delays associated with shipping from Bangkok.  Also at the moment, they are closed for a National Holiday week.

The cases from https://amateurradiokits.in/ are pretty neat and are pre-punched and come with all the associated goodies.  The selections available vary from day to day,  so far they haven't had the "one" I liked best available.  I think these are an excellent bargain considering the goodies bag they came with.

73 Jack KZ5A

On 4/17/2019 5:30 AM, Lawrence Galea wrote:
Sorry about it folks
Probably the copy and paste didn't work and the previous link was posted instead.
Here is the correct link and I checked it 

https://www.banggood.com/250x190x110mm-Blue-Metal-Electronic-Enclosures-DIY-Power-Junction-Box-p-1067251.html?cur_warehouse=CN 

Wishing everyone a happy Easter



On Tue, Apr 16, 2019 at 11:23 PM Jim <Jscook@...> wrote:
That is a good recipe. Have to try it. Grin


On Apr 16, 2019, at 5:11 PM, Karl Heinz Kremer, K5KHK <khk@...> wrote:

Is this a new form of rick rolling? ;) Or are you suggesting we should leave our radios turned off on Easter and to enjoy a sweet treat instead? Or, did you post the wrong link?

--
Karl Heinz - K5KHK



--
Keith Baker - Communications technician (retired)


Re: Homebrew li-ion battery pack into ubitx

Clark Martin
 

Ah, you picked the good one, based on a Linear Technology chip.  Many Buck-Boost converters will not operate well near unity (Vin = Vout), but this one does.  I’m using one as a built in charger for a LiFePO4 battery pack and another for a general purpose charger with adjustable output.

On Apr 17, 2019, at 7:55 AM, Bill Lamm <kd9mdl@...> wrote:

 I have been looking at Drok's sight this morning.. love reading the reviews 😶  found this Drok buck boost that looks like I can set to 12.x volts out and either plug in a 13.5v PS in the shack or a lipo or whatever battery.. on or off solar panel and it will give me 12.x volts all day..   I am no ex-spurt so if any of you see something I am missing I welcome the wisdom..  for a start I am thinking or one and then if it pans out that sending more power to the finals is a good thing I would consider a second one..   my (up purpased) case has room, I am planning seperate fast acting fuses for the raduino (1.5a) and main board (2a or 3a)... still sorting through the polarity protection options but I have power pole connectors for the power connection on the case..


Re: Homebrew li-ion battery pack into ubitx

Adrian Chadd
 

Hi!

So I'd like to do this but with a good old SLA battery. What suggestions do people have for inline charge controllers? I'd like to keep the battery topped up when I'm running on the radio but run off the battery as well.

I know I can make a trickle charger with a current limiting supply .. :)


-a

Re: Homebrew li-ion battery pack into ubitx

Evan Hand
 

If you want to build from scratch:
https://www.maximintegrated.com/en/app-notes/index.mvp/id/621?gclid=CjwKCAjwndvlBRANEiwABrR32HIAgCd0XiHWPrfMf9p1y_aZAZpPVVTB46osHNQCah1GIGUB4PiRJBoCmnYQAvD_BwE

Otherwise just buy a trickle charger for the SLA.

just a suggestion, you may find other better choices.

73
Evan
AC9TU

Re: Homebrew li-ion battery pack into ubitx

Jerry Gaffke
 

Way down in the fine print of that Drok switcher, it says:  "With constant voltage, constant current and under-voltage protection."
So, does it have a knob that allows you to set output current max to anything between 0 Amps and 10 Amps?
I would expect that to be proclaimed loudly up in the title, as it would be a significant enhancement over most of the cheap switchers.

Yes, it is a bit of a trick to get a buck-boost switcher to operate smoothly in the region between buck and boost where Vin = Vout
If this does provide adjustable current limiting, does up to 30 Watts within the limitations of 10 Amps max (I assume in or out),
30 Volts (out) max, and smoothly does the buck-boost thing, it's well worth the money they are charging.
This plus an old laptop power brick and meters for voltage and current would make an excellent bench supply for the hobbyist.

Jerry, KE7ER


On Wed, Apr 17, 2019 at 10:04 AM, Clark Martin wrote:
Ah, you picked the good one, based on a Linear Technology chip.  Many Buck-Boost converters will not operate well near unity (Vin = Vout), but this one does.  I’m using one as a built in charger for a LiFePO4 battery pack and another for a general purpose charger with adjustable output.

 
toggle quoted message. . .

 

On Apr 17, 2019, at 7:55 AM, Bill Lamm <kd9mdl@...> wrote:
 I have been looking at Drok's sight this morning.. love reading the reviews 😶  found this Drok buck boost that looks like I can set to 12.x volts out and either plug in a 13.5v PS in the shack or a lipo or whatever battery.. on or off solar panel and it will give me 12.x volts all day..   I am no ex-spurt so if any of you see something I am missing I welcome the wisdom..  for a start I am thinking or one and then if it pans out that sending more power to the finals is a good thing I would consider a second one..   my (up purpased) case has room, I am planning seperate fast acting fuses for the raduino (1.5a) and main board (2a or 3a)... still sorting through the polarity protection options but I have power pole connectors for the power connection on the case..

Re: N6DT AGC and S-meter

rickaputi@...
 

thanks for all the input, guys!!!   i love this group!  guess i may have to try the lm385 op amp. tried using lots of different values in the memory manager for the s-meter adjustment.  i did use the "S" firmware, assuming that the "S" referred to the s-meter addition.  will try the other firmware, only takes a few minutes to do.  will report on the results. thanks again! Rick WA2TDL.

Re: Homebrew li-ion battery pack into ubitx

Bill Lamm
 

I have a turnigy charger that has those plugs on the side for the batteries I have (and bigger) I will most probably leave the battery(s) external. My plan is to keep things modular (power, antenna tuner, etc) until I know what is working best and/or I can use on other rigs.. ultimatly it should all transition easily from shack to pack or pelican case...

Re: Homebrew li-ion battery pack into ubitx

Doug W
 

On Wed, Apr 17, 2019 at 12:37 PM, Jerry Gaffke wrote:
So, does it have a knob that allows you to set output current max to anything between 0 Amps and 10 Amps?
That caught my eye too so I did some more looking.  That module looks to be the same as https://www.aliexpress.com/item/Auto-Buck-Boost-Power-Supply-Module-DC-5-32V-to-1-30V-10A-80W-Adjustable-Voltage/32510686551.html which about 1/2 way down the listing labels some of the components.  The middle trimmer is shown as constant current regulation.
 
--
www.bitxmap.com

Re: Homebrew li-ion battery pack into ubitx

Bill Lamm
 

I believe it does.. if you follow the (Drok buck boost) link in my original post it is at Drok's sight with details.. several reviews described using it to regulate a source that could be higher or lower then target output with exceptable (to them) results..  If I understand correctly the lower the input voltage the higner its amp potential needs to be (over target) to maintain the amps we want at target (12.5 volt 3 amps for basic kit?)

Re: Homebrew li-ion battery pack into ubitx

Jerry Gaffke
 

Might not be ideal with regard to current limiting. 
From the Amazon reviews:

"At first, I had some trouble with the CC adjustment apparently not working. It would always run at the full 60W, or about 5A, regardless of how I adjusted the trim pot. I tried three of these modules before I realized that this behavior occurs only when I have the IN and OUT grounds in common, i.e. both attached to the same terminal strip. If I separate them so that there are completely separate grounds for the charging source (IN) and the battery (OUT), then the constant current adjustment works as expected..
While my particular battery can accept a 5A charging current, when the module is running at its 60W upper limit the heatsink gets really hot. If limited to 2A (about 25W), the waste heat is significantly reduced, enough to be comfortable with keeping the module in an enclosed battery box.
I did also see the "bouncing" behavior mentioned by the other reviewer when using a smaller power source. The solution of a 1uF capacitor and 1M Ohm resistor soldered into the "KEY" contacts appears to solve this problem.
Deducting 1 star for the lack of any published data sheet or instructions, although some info is available via the Drok web site."

So sounds like current limit occurs in the return leg coming back from the load.
Lots of other comments about current limit not working, the above comment is the key to this.
An unfortunate design flaw.


"
So far works well. I've used it to build a cheap bench power supply for future projects by replacing the built in potentiometers with ones you can turn without a screwdriver (you need two 500k and one 200k) The current limit pot works on mine unlike one of the other reviews (maybe they had a dud), the undervoltage protection control works and the voltage control works but not quite to what is specified. The response time to a change in load wasnt hugely fast. I can't remember how fast, if you want to see an oscilloscope plot just ask. The only other gripe is that the power in and out ports could have been a little more rugged."

"A great DC/DC power converter. I used it in a manner that it wasn't necessarily intended for - in a bench power supply that is voltage adjustable and current limited. Be advised - the current is only able to be limited down to about 100 ma (which is better than the stated spec at 200 ma) - which is very good for it's stated application - but not perfect for a current limited power supply !!! Also - if you remove the on-board voltage / current limit multi-turn pots - the de-soldering process can ruin the board traces - ruining the device for adaptation. I ended up getting another one - and carefully cutting and crushing the on-board pots - preserving the 3 original leads coming from the board. Then I wired external pot leads to the existing leads. Worked perfectly"


If you do replace the pots, be sure to use quality pots.  Or at least check the design of this thing
to see if a dirty pot might make voltage or current regulation jump high instead of low.


"It"s a tight fit but you certainly can upgrade the main filter cap to 50v. An extra 470 uF on top of that benefited the output signal significant"

"Morever, unlike others I have tested, this one doesn't produce RF hash to it can be used near radios."

Though our Bitx radios are more sensitive to power supply noise than most due to the high gain audio amps.

"
NOW..... the photo has changed. This is NOT the supply that I received in my last few orders. The photo shows a power supply that I have used in the past until recently."

So this particular Amazon item can change?

In the usual Amazon fashion, the reviews section is for a range of different DROK products.
Since folks don't realize this they don't bother specifying exactly which DROK product they have on hand.
Very unfortunate.  And just plain stupid on the part of whoever set up the review scripts.

Jerry, KE7ER


On Wed, Apr 17, 2019 at 10:37 AM, Jerry Gaffke wrote:
Way down in the fine print of that Drok switcher, it says:  "With constant voltage, constant current and under-voltage protection."
So, does it have a knob that allows you to set output current max to anything between 0 Amps and 10 Amps?
I would expect that to be proclaimed loudly up in the title, as it would be a significant enhancement over most of the cheap switchers.

Re: Homebrew li-ion battery pack into ubitx

Jerry Gaffke
 

Conservation of energy demands that Watts out be no more than Watts in.
Watts = Volts * Amps
So if, for example, you are feeding 12v in and have it adjusted for 24v out, and have a load asking for 1 Amp,
then the 12v input will have to be taking at least 2 Amps from your power source.
It will burn up some power as heat due to inefficiencies, so might be more like 2.5 Amps going in.


On Wed, Apr 17, 2019 at 11:11 AM, Bill Lamm wrote:
I believe it does.. if you follow the (Drok buck boost) link in my original post it is at Drok's sight with details.. several reviews described using it to regulate a source that could be higher or lower then target output with exceptable (to them) results..  If I understand correctly the lower the input voltage the higner its amp potential needs to be (over target) to maintain the amps we want at target (12.5 volt 3 amps for basic kit?)

Re: read/write with ubitx manager #ubitx-help

Cristian (YO8SXT)
 

thanks.....is a good ideea....i am planing in the future to add a nextion display.....thanks for the help

Pe miercuri, 17 aprilie 2019, <radiomanyo@...> a scris:

Hello Cristi !

uBitx manager does not work with original firmware.It works only with CEC firmware. Please read article about how to make work the manager with original Fahran's firmware on Ian's site : hamskey.com. The problem is to store the original alignment  values and apply them to CEC firmware. Not sure but maybe the solution is on Ian's site. In worst case scenario you have to make a new alignment following the instructions again from Ian' site. It worth to go with the latest CEC firmware, it is compatible with all versions of uBitx and supports LCD 16x2,16x4, or nextion display.Has a lot of new features nonexistent at original firmware. Hope it was useful.
73.s yo6po

grounding #ubitx #ubitx-help

Dennis KL4LG
 

   Radunio powers on when plugged into a usb source
   ubitx powers on when not mounted in metal case
   raduino and ubitx power on together when not in metal case

never had to ground any of my other random duino/pi toys

  does the metal enclosure need to be grounded to earth ground?

I am either digging the wrong hole or asking the wrong questions, because I just can't seem to find it.

thanks,
Dennis KL4LG