Re: RF power chain mods and improvements..
Even a BS170 (TO92) would work as a pre driver. However perhaps MPSH10 (MMBTH10 in sot23) just sits on the uBITX board and would do well i suppose
On Sun, May 20, 2018 at 9:02 AM, ajparent1/KB1GMX <kb1gmx@...> wrote: Problem with 2sc1973 is they may be hard to get and its still a 300mhs ft.? Might as well use 2n2222a.
The Bf199 is likely better save for its 25V CE breakdown is kinda low but the 1100mhz FT would be better.
I'd not use it for the 25V breakdown spec.
RIght now I'm not pulling transistors at random.
Q90 a 2n2963A in a smt form is being tried at 19 ma I think the current is too
high and I may reduce it further to 10-15ma. It only has to produce 2mw of power
max so running more than 200mw of power is excessive. At 15ma its about 185mw
being dissipated.? Why waste power.
Q911/912:
What I think we should use for pre-driver something with a 500 to 1ghz FT, .6 w or
better per device.? ?The HFE at higher current (30-50ma) must not sag. Even at
that the stage only need produce less than 100mw (more like 70).? ?One device
is not stressed doing that.??
Q92/93/96/97:
What I think we should use for driver something with a 500 to 1ghz FT, 1 w or?
better per device.? ?The HFE at higher current (50-100ma) must not sag.
THis stage is push pull and two need to be able to push about 1 watt
and there are many that can do that as two rather than 4.? It also can run
class AB1 at about 10 to 20ma per device since its push pull.? The
device current as is with 3904s is 27ma (very high) per device on mine.
Candidates I know of but not tested are:?
MPSH10 but I have to try them.
2n2222A? its worked in the past but the FT is barely enough.
2n3553//2n3866/2n5109 are likely good for driver (2 not four).
And no, don't go out and buy them unless your experimenting on your own.? Do report
your results!? More data points may be important.
Before the CW key oddity happened? I was testing a lone (1 not wo) and the predriver
and was getting the same or more power. makes sense as we only need maybe
70 mw of power there.? Not tested enough so everyone sit down please till it is.
I have? no reason to change the IRF510s.? For 10-12W its just right.
Allison
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Re: pin 2 of raduino board seems to have gone to CW TX full time after boot message.
Allison you should check your 4.7k resistor solder connections you should be measuring 5vdc on both sides and ground. Pin 3 is the 5vdc supply and the 4.7k resistor is setting pin 2 high. Do you have the CW jack wired up. If so what is plugged into it, that could be what is drawing low enough to switch into transmit.
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On May 19, 2018, at 22:56, ajparent1/KB1GMX < kb1gmx@...> wrote: Odd issue popped up while working with the transmitter.
Radio went to CW and stayed keyed.? Tried power of and suoon as it booted it went CW and keyed.
This is odd as the blue, purple, and green wires are not even in the connector as i"m not using the key.
The 4.7K resistor is in place on the green/blue connection pair.
If I measure pin2 (blue) to ground I get .1V save for ther is no connection and it ohms open (power off).
If I connect blue to +5 it stops but the pin is pulling down 25ma!
No ESD likely strap and conductive pad in use.
If I didn't know better id swear the input self reprogrammed as an output!
I may have to do the programing dance on this before pulling the nano.
Firmware is? factory v0.20 on startup.
Any thoughts?
Allison
|
Base on that diagnostic and the other test you run I would say definitely the Nano has an analog input issue.
In my test, when you turn the encoder only one way it should always say either incrementing or decrementing but not alternating between the two.
That would explain why your frequency hardly changes when you turn the encoder.
Jim Sheldon (W0EB) had a few defective Nanos, some brand new, and they failed the encoder test of the diagnostic software too.
So it looks like it's (de)soldering time unfortunately.
I had to change my Nano for a different reason and I didn't manage to remove it as cleaning as yesterday's example, but it works.
Regarding SMDs, I until now, always used through hole, but I am sold on SMDs now, thanks to the advice on this forum. I really like the density of the circuits and if you get the few inexpensive tools to handle them it is not difficult. I bought one of these 1206 size component sample books from eBay (or elsewhere) which contains all valuable values and more of resistors and some of even capacitors.?
You'r right, maybe time to upgrade the Raduino too.?
Thanks for the link. I will see how that is done and maybe get some ideas to improve my test software.
All the best,
73, John (VK2ETA)
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Does the Blink or ASCII Table example programs run?
Jack, W8TEE
On Saturday, May 19, 2018, 11:32:40 PM EDT, Kd4epg@... <Kd4epg@...> wrote:
John,
I failed to include the link to the encoder test routine.. here it is..
I changed the pins from 2,3 and 4, to 14, 15 and 16 to accomodate the Raduino. I took the board off the mother board, disconnected the cable, used a bread board and wires to connect up directly from breadboard to Raduino and ran your program and the Encoder test. I can get the button to work but nothing on the encoding. I am becoming more convinced I have a bad Nano board. The encoder and breadboard works just fine when I use a new Nano and your program and the encoder check program.
Thanks for your help.
Guess I will have to learn how to solder SMD right quick and get one of Jim Sheldon's kits working. here.. or make my own..
--
72 and God bless
KD4EPG
|
Re: RF power chain mods and improvements..
Problem with 2sc1973 is they may be hard to get and its still a 300mhs ft.? Might as well use 2n2222a.
The Bf199 is likely better save for its 25V CE breakdown is kinda low but the 1100mhz FT would be better.
I'd not use it for the 25V breakdown spec.
RIght now I'm not pulling transistors at random.
Q90 a 2n2963A in a smt form is being tried at 19 ma I think the current is too
high and I may reduce it further to 10-15ma. It only has to produce 2mw of power
max so running more than 200mw of power is excessive. At 15ma its about 185mw
being dissipated.? Why waste power.
Q911/912:
What I think we should use for pre-driver something with a 500 to 1ghz FT, .6 w or
better per device.? ?The HFE at higher current (30-50ma) must not sag. Even at
that the stage only need produce less than 100mw (more like 70).? ?One device
is not stressed doing that.??
Q92/93/96/97:
What I think we should use for driver something with a 500 to 1ghz FT, 1 w or?
better per device.? ?The HFE at higher current (50-100ma) must not sag.
THis stage is push pull and two need to be able to push about 1 watt
and there are many that can do that as two rather than 4.? It also can run
class AB1 at about 10 to 20ma per device since its push pull.? The
device current as is with 3904s is 27ma (very high) per device on mine.
Candidates I know of but not tested are:?
MPSH10 but I have to try them.
2n2222A? its worked in the past but the FT is barely enough.
2n3553//2n3866/2n5109 are likely good for driver (2 not four).
And no, don't go out and buy them unless your experimenting on your own.? Do report
your results!? More data points may be important.
Before the CW key oddity happened? I was testing a lone (1 not wo) and the predriver
and was getting the same or more power. makes sense as we only need maybe
70 mw of power there.? Not tested enough so everyone sit down please till it is.
I have? no reason to change the IRF510s.? For 10-12W its just right.
Allison
|
John,
I failed to include the link to the encoder test routine.. here it is..
I changed the pins from 2,3 and 4, to 14, 15 and 16 to accomodate the Raduino. I took the board off the mother board, disconnected the cable, used a bread board and wires to connect up directly from breadboard to Raduino and ran your program and the Encoder test. I can get the button to work but nothing on the encoding. I am becoming more convinced I have a bad Nano board. The encoder and breadboard works just fine when I use a new Nano and your program and the encoder check program.
Thanks for your help.
Guess I will have to learn how to solder SMD right quick and get one of Jim Sheldon's kits working. here.. or make my own..
--
72 and God bless
KD4EPG
|
Re: Core for Output Transformer
Hi all,
Have been following this thread keenly and modding and checking at stages on the way.
Completed in the following order.
Q90 to 2n2222a sot23.
220pf caps on all 7 driver chain emitter resistors.
MPSH10 in for the next two.
All good up to here. Drive pot at halfway. 14w at 40m, 3w at 10m. Power 13.8v. ?Each step showed some improvement in power at 10m (which started at 1w).
Next step - next 4 transistors changed to MPSH10 and things go backwards. Power at 10m down to 1.5W and power on lower bands is less also.
hfe on the MPSH10 ranged from 120 to 135. 2n3904 were much higher.
No other changes made so everything else stock in the transmit chain. Even at full RV1 I cannot achieve power levels I was getting before the last step.
Wasnt expecting this result and wondering if Ive got some dud MPSH10 to replace.
Regards
Simon VK3ELH?
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Hi Mike,
Its worth the efford to replace the
You will need a , a and a . Most likely a .
Clean the solder joints with alconhol, melt the solder and press the solder sucker over the ping while the tip of the iron is still heating the solder. And suck the solder away! Repeat twice per pin. I also ended up desoldering the bleu board on the other side and pulled the boards appart. Pulling the remaining pins was easy.
Clean evertything up and make sure the holes are open (use a paperclip). Installing the new Arduino Nano is easy.
Good luck!
ROgier
|
pin 2 of raduino board seems to have gone to CW TX full time after boot message.
Odd issue popped up while working with the transmitter.
Radio went to CW and stayed keyed.? Tried power of and suoon as it booted it went CW and keyed.
This is odd as the blue, purple, and green wires are not even in the connector as i"m not using the key.
The 4.7K resistor is in place on the green/blue connection pair.
If I measure pin2 (blue) to ground I get .1V save for ther is no connection and it ohms open (power off).
If I connect blue to +5 it stops but the pin is pulling down 25ma!
No ESD likely strap and conductive pad in use.
If I didn't know better id swear the input self reprogrammed as an output!
I may have to do the programing dance on this before pulling the nano.
Firmware is? factory v0.20 on startup.
Any thoughts?
Allison
|
Rogier
CONGRATULATIONS
Linux Just Works.
Arv
_._
On Sat, May 19, 2018 at 8:26 PM, kj6etl <pa1zz@...> wrote: !SUCCES!
A roadkill computer came to the rescue...
After readig that the Arduino Nano migth have trouble with the USB 3.0 ports on my iMac I installed the software on my older MB Pro loaded the USB drivers and connected the Arduino. Only to be greated with a immidate shutdown! Not just any shutdown I had to reset the PRAM and reboot in Safeboot to get the MB pro runnning High Sierra 10.13.4 up and running again. After a couple of attempts I gave up and resurected an old HP laptop from the trash. Pulled some Memory and SSD drive from my junk box installed into this roadkill laptop and loaded Ubuntu. Next was the Arduino software ad KD8CEC software. At first the board was barking at me all sorts of errors needed to be googled and implemented. After a brief battle for permissions I was able to load the KD8CEC software and the Arduino turned into a Raduino!
Next step was connecting it to the dismembered parts on the cutting board and apply power.
ITS A LIVE!
|
Re: ND6T AGC implementation for uBIT-X
@Kees
I noticed that Andy - N9TGR was added to the requested list, it's actually meant to be Ramsin Israel - N9RLI (I'm ordering them for both me and Andy). Thanks!
Also, when/how do I pay?
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Thanks for the suggestion, Bob. I tried that. The ground is fine, the voltage is near +5v as supplied by the NANO as a reference. I took the power down, disconnected from power source and checked the ground to chassis ground and it is good. Great idea, just not the solution here.
The good news is, I am learning more than I wanted to know about encoders.. lol..
--
72 and God bless
KD4EPG
|
!SUCCES!
A roadkill computer came to the rescue...
After readig that the Arduino Nano migth have trouble with the USB 3.0 ports on my iMac I installed the software on my older MB Pro loaded the USB drivers and connected the Arduino. Only to be greated with a immidate shutdown! Not just any shutdown I had to reset the PRAM and reboot in Safeboot to get the MB pro runnning High Sierra 10.13.4 up and running again. After a couple of attempts I gave up and resurected an old HP laptop from the trash. Pulled some Memory and SSD drive from my junk box installed into this roadkill laptop and loaded Ubuntu. Next was the Arduino software ad KD8CEC software. At first the board was barking at me all sorts of errors needed to be googled and implemented. After a brief battle for permissions I was able to load the KD8CEC software and the Arduino turned into a Raduino!
Next step was connecting it to the dismembered parts on the cutting board and apply power.
ITS A LIVE!
|
Re: rough draft of how to connect BITX to PC for digital modes wiki
Looks like the DTR pin is in the row marked K2 next to resistor R4. Mike K5ESS ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Dennis
Sent: Friday, May 18, 2018 9:04 PM
To: [email protected]
Subject: Re: [BITX20] rough draft of how to connect BITX to PC for digital modes wiki ? Hi Doug,
I would like to use the following part instead of a FTDI cable. Can you tell me which pin out is for DTR??
Thanks for any help.
73, Dennis
W7DRW
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John,
Ran across this neat little sketch to test encoders. I used a new NANO and used this sketch straight up. All? of my encoders test good. However, I did learn a thing or two. One batch of encoders, the KY-40 version, occasionally puts in a 255 for the value when you are expecting a 0, 1, 2 or 3 for the output. The other batch never did do that.. The one without the board .. However those don't have the switch, so I will order me some from Mouser or Digi and get a replacement...
Still, that doesn't answer my questions about the frequency. think maybe an input on the nano is bad?
--
72 and God bless
KD4EPG
|
Re: RF power chain mods and improvements..
What about using (2) 2SC1973s for the drivers and BF199s as the pre-drivers?
Marco - KG5PRT?
On Sat, May 19, 2018, 5:08 PM ajparent1/KB1GMX < kb1gmx@...> wrote: Hi Arv,
Yes. But there is no need for that.? We need under 1W to drive a IRF510
to 10 ore more watts.? Actually I've used 2W in the WA1EBY (pp pair of
IRF510s at 28V) for more than 50W.? To get 2W I used a 2SC779 and it
as not working hard at all.
Work backwards if you want 10W assume worst case 10DB (Likely 13-16)
so to get 1 you only need 1W if its 13DB its .5W, and so on.? The trick is
to load the gate so the IRF510 is stable? and make it up with drive power.
The bigger parts like the IRF520 and 530 are sill power limited due to heat transfer
though it is better the problem is efficiency keeping it above 45% so your not
equally heating the device for every watt you put out as the dissipated power is
your limit. And IRF510 at 3A 12V is handling 36W, if the efficieny is 50%
your seeing 18W.? Save for its needs 24V to do that and then you are at 72W
input and 36 out (eff=.5).? The part is 4+ amp capable so that not a limit. The
limit is the 36W of heat.? One must deliver that power to the load not as heat.
Allison
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Re: Ashhar Farhan Inducted into CQ Amateur Radio Hall of Fame
Farhan?
How well deserved. I wished I had known I would have made the time to get away from our booth here in Xenia to witness the award.
We¡¯ve had a blast with our two uBITX.
Dave WI6R ? Radiosport headsets
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On May 19, 2018, at 9:29 PM, ajparent1/KB1GMX < kb1gmx@...> wrote: Its a good thing that what you do benefits others and gets recognized for the effort.
Congratulations!
Allison
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Re: Top-side ground plane?
Mostly because its not needed and adds complexity for little value.? If it were then a 3 or four
layer board might be justified but modding such a board is never easy.
Try fixing a board error (short circuit) in a 10 layer board, just drill here... exactly!? Oops!? ;)
Allison
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Re: Ashhar Farhan Inducted into CQ Amateur Radio Hall of Fame
Its a good thing that what you do benefits others and gets recognized for the effort.
Congratulations!
Allison
|
The STMfxxx is a arm based cpu and available on small board and a few no so small ones too.
Its a 32bit cpu with lots of speed cor more complex tasks or needed capability.
The Arduino is generally based on the ATmega series of chips with the atmega328 being the
common one.? The Atmega is an 8 bit cpu that is very fast but smaller.? Its sill very capable and
can do a lot of things.
The difference is like a skooter and a rocket.? They both move but well, they are different!? ;)
FYI there are board in the arduino ecosystem that are 32bit and all but they aren't used here.
Allison
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Skip Davis
kj6etl