Re: #ubitx New I2C/Digital I/O mod & firmware from W0EB/W2CTX
#ubitx
Bob, I think after I posted that, Amazon ran out of them. ?Any I2C controller should work as long as it can provide 5 volts to the LCD display while talking on the I2C bus with only 3.3 volts to keep from smoking the VFO generator in the uBITX. ?
If the controller uses the PCF8574 chip and does NOT have pull up resistors to 5 volts (around 4.7K) on pins 14 and 15 of the chip it should work. ?If it does have resistors on pins 14 and 15 just unsolder them and it will still work. ?The lines used for SDA and SCL in the PCF8574 are "open drain" in the chip so it can actually talk to the Nano reliably on the I2C bus without those reisistors as it will use the pullups to 3.3V in the Si5351. ?Almost zilch current draw there so no problem.
There are different suppliers on Amazon that sell that same controller - Here's a photo of the board itself on the back of the display (I believe this picture is in the hardware manual I sent -). ?It's the one with the LED lit up on it. ?The two resistors that were removed are the two that were right next to the PCF8574 chip on the same row as the LED. ?Do a search on I2C controller and hopefully you will find one of them.
Jim
------ Original Message ------
Sent: 1/27/2018 3:30:51 PM
Subject: Re: [BITX20] #ubitx New I2C/Digital I/O mod & firmware from W0EB/W2CTX
Great work!
In the doc you mention the need to be careful in selection of the I2C display controller and talk about a board from Amazon by seller "IC Module". Would provide a link? My search for IC controller on Amazon doesn't turn up one from that seller.
??? Bob?? KD8CGH
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Re: #ubitx new Alternate software for the uBITX
#ubitx
Thanks Great Firmware.
It's works my ubitx very well.
I modify two small function.
#1 TX only ham bands
It MUST need Japan reglation.
(Japan need Application for Transmitter spec inspection.)
In main loop,Check current frequency,It's valid,ham band,process sense key or PTT .
#2 In CW mode, Push PTT to TX CW(every Straght key mode)
For emagency use and ATU tune.
External key or paddle works nomally menu setting.
This is my blog(Sorry,Japanese)
de JE4SMQ masa
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Re: UBITX Touch Control TFT Display
Re guarding SI5351
Boards, I still have Bare PCBs that are stand alone I2C 5V
driven.
They can have headers
top or bottom for connectors or plug in.
They both have proper
level translation for I2C with 3.3V regulators.
The larger one is
Lotsa Clocks, has the 20 Pin SI5351 with extra address jumper
and 8 Clocks.
Here is a picture of
them.? Bare and stuffed.
The bare PCB is $4 and
$6 for Lotsa Clocks.? Include postage US and PayPal.
email me direct if
interested.
73's
Mike, WA6ISP
On 1/27/2018 7:40 AM, Jerry Gaffke via
Groups.Io wrote:
I had never heard
of elegoo.com, that looks like a good steer.
They have some nice Arduino starter kits.
However, their 2.8" TFT display is not well documented, and burns
an awful lot of pins.
Here's a reply to a question up on Amazon:??
? ? ??I just went through all of
the pins marked on the board and the code for the support
libraries.
? ? ? It appears that the display hogs all of the pins with the
exception of the A5 and the serial I/O pins 0 and 1.
? ? ? This pretty much precludes the use of any other peripheral
devices using Wire, SPI, or I2C.
? ? ? The SD card uses digital pins 10 through 13, so if you
don't need the SD card, you can snip those pins off
? ? ? (and don't include the SD library in your project).
Otherwise the options are limited.
Not what I'm looking for.??
I'd prefer a display with just a 4 wire SPI interface, and power
and ground.
Recommendations solicited.
Regarding the si5351 PLL chip breakout board, in addition to
adafruit.com, there is also etherkit.com and qrp-labs.com
Hans of qrp-labs is active on this forum, a kit for his board is
$7.75
? ??
The others come fully soldered up, which some may prefer.
Jerry, KE7ER
On Fri, Jan 26, 2018 at 06:42 pm, Joe wrote:
Brein,
?
I use the
following: HARDWARE
?
DISPLAY?-
Optimum size - 2.8inch TFT - I have tried several types and
sizes from various companies - hit and miss. some work but
poor clarity etc.
?
Having used the?elegoo
2.8 inch? TFT Display with pen - from "amazon"?has
resulted in 100 percent working, clear, clean, crisp displays.
I have ordered
4 over time and quality is persistent. Price? around $15.00
shipped.? Best choice
?
?
Arduino
Module?: Atmega 2560 - Ebay is
cheapest source at less then?$10.00...?
Any Atmega 2560 will work..
I have many
different company modules and have found they all work
great...
?
DDS module -?
SI5351??module?(not
just the chip)- available from Ebay or Adafruit direct or
amazon around $11.00
?
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
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Just like to ask have you got power on the FETs I not seen the circuit for the ubix as I not got? mine yet chris
On 27 Jan 2018 21:46, "César EA3IAV" < Cesarleon@...> wrote: 200 on receive
500 on tx but it doesn’t flick when talking or ? whistling
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Re: uBITX Firmware (CEC) 0.30 released (Test version).
#ubitx
Thanks Jim,
I need to order some more chip resistors anyway so your input is helpful.
toggle quoted message
Show quoted text
On Jan 27, 2018, at 1:28 PM, Jim Sheldon < w0eb@...> wrote: Good Idea Dave, I did that on one of mine earlier. ?I used 1206 size, but 0805 might fit better. ?No current so wattage is not a factor.
Jim - W0EB
------ Original Message ------
Sent: 1/27/2018 3:14:50 PM
Subject: Re: [BITX20] uBITX Firmware (CEC) 0.30 released (Test version). #ubitx
Ian?
The v.30 with Ron’s CW Keying code does include adding the 4.7k pull-up at A7, as a modification to hardware.
I’m planning on adding both 4.7K chip resistors directly on the pads of the Raduino so there are no loose resistors to mount at the key jack(s).
Dave WI6R Sent from my iPhone On Jan 27, 2018, at 2:39 AM, Ian Lee < kd8cec@...> wrote: I have not posted it on my blog separately since it is a test version. When the test is complete, ?write a usage and post it. I am writing for someone who is interested and test.? If I get an error report or a fix, I'll fix it and make it into github's 0.31 branch. Here is a brief description of the change from 0.30. improved CW Keying, Frequency Tune and CW performance according to users' requirements. In particular, CW Keying applied ron's logic for use with original hardware. also made it possible to set the CW Key ADC range to reduce errors in CW. ADC monitoring function is added to know the exact resistance and key contact status.
I thought that if you set your own ADC range using the measured values here, you would get an error.?I need to test these things, so I leave this post. removed all existing sources related to frequency tune.?And i applied threshold, weight about speed, and steps. The problem of changing the frequency at the moment of catching the knob has probably disappeared. when the threshold has been exceeded, start frequency changing,?i added some logic to prevent the thresholds from becoming unnatural. If you want to fine-tune, slowly turn it and the threshold will be applied continuously and change very slowly. The tune steps you can select now are 10, 20, 50, 100, 200, but you can change them in uBITX Manager 0.31 (now working)
You can change the step by pressing the function key for a long time. If you keep pressing it, Diallock will work.
The ham band movement applied at 0.28 was set to 0.30, so that region1 was set as the default.
Of course, you can change to the previous operation state by pressing the function key in the band select menu for a long time.
And like the 0.28 version, you can set up to 10 frequency bands in uBITX Manager to suit your country or your liking.
Please refer to below for the improvements and how to upload firmware and more detail. The source and compiled firmware can be found in the release below link.
How to upload firmware and use version up to version 0.27
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
|
200 on receive
500 on tx but it doesn’t flick when talking or ? whistling
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Re: #ubitx New I2C/Digital I/O mod & firmware from W0EB/W2CTX
#ubitx
Great work!
In the doc you mention the need to be careful in selection of the I2C display controller and talk about a board from Amazon by seller "IC Module". Would provide a link? My search for IC controller on Amazon doesn't turn up one from that seller.
??? Bob?? KD8CGH
|
Re: uBITX Firmware (CEC) 0.30 released (Test version).
#ubitx
Good Idea Dave, I did that on one of mine earlier. ?I used 1206 size, but 0805 might fit better. ?No current so wattage is not a factor.
Jim - W0EB
------ Original Message ------
Sent: 1/27/2018 3:14:50 PM
Subject: Re: [BITX20] uBITX Firmware (CEC) 0.30 released (Test version). #ubitx
Ian?
The v.30 with Ron’s CW Keying code does include adding the 4.7k pull-up at A7, as a modification to hardware.
I’m planning on adding both 4.7K chip resistors directly on the pads of the Raduino so there are no loose resistors to mount at the key jack(s).
Dave WI6R Sent from my iPhone On Jan 27, 2018, at 2:39 AM, Ian Lee < kd8cec@...> wrote: I have not posted it on my blog separately since it is a test version. When the test is complete, ?write a usage and post it. I am writing for someone who is interested and test.? If I get an error report or a fix, I'll fix it and make it into github's 0.31 branch. Here is a brief description of the change from 0.30. improved CW Keying, Frequency Tune and CW performance according to users' requirements. In particular, CW Keying applied ron's logic for use with original hardware. also made it possible to set the CW Key ADC range to reduce errors in CW. ADC monitoring function is added to know the exact resistance and key contact status.
I thought that if you set your own ADC range using the measured values here, you would get an error.?I need to test these things, so I leave this post. removed all existing sources related to frequency tune.?And i applied threshold, weight about speed, and steps. The problem of changing the frequency at the moment of catching the knob has probably disappeared. when the threshold has been exceeded, start frequency changing,?i added some logic to prevent the thresholds from becoming unnatural. If you want to fine-tune, slowly turn it and the threshold will be applied continuously and change very slowly. The tune steps you can select now are 10, 20, 50, 100, 200, but you can change them in uBITX Manager 0.31 (now working)
You can change the step by pressing the function key for a long time. If you keep pressing it, Diallock will work.
The ham band movement applied at 0.28 was set to 0.30, so that region1 was set as the default.
Of course, you can change to the previous operation state by pressing the function key in the band select menu for a long time.
And like the 0.28 version, you can set up to 10 frequency bands in uBITX Manager to suit your country or your liking.
Please refer to below for the improvements and how to upload firmware and more detail. The source and compiled firmware can be found in the release below link.
How to upload firmware and use version up to version 0.27
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
|
Yes, current goes up when PTT is pressed because the rig is now powering
the four stages of the transmit power amp, starting with Q90.
How many mA on receive?
How many mA on transmit?
toggle quoted message
Show quoted text
On Sat, Jan 27, 2018 at 12:52 pm, César EA3IAV wrote:
but when I have it like this i have much more mA when ptt than if it is turned a bit counterclockwise
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Re: uBITX Firmware (CEC) 0.30 released (Test version).
#ubitx
Ian?
The v.30 with Ron’s CW Keying code does include adding the 4.7k pull-up at A7, as a modification to hardware.
I’m planning on adding both 4.7K chip resistors directly on the pads of the Raduino so there are no loose resistors to mount at the key jack(s).
Dave WI6R
toggle quoted message
Show quoted text
On Jan 27, 2018, at 2:39 AM, Ian Lee < kd8cec@...> wrote: I have not posted it on my blog separately since it is a test version. When the test is complete, ?write a usage and post it. I am writing for someone who is interested and test.? If I get an error report or a fix, I'll fix it and make it into github's 0.31 branch. Here is a brief description of the change from 0.30. improved CW Keying, Frequency Tune and CW performance according to users' requirements. In particular, CW Keying applied ron's logic for use with original hardware. also made it possible to set the CW Key ADC range to reduce errors in CW. ADC monitoring function is added to know the exact resistance and key contact status.
I thought that if you set your own ADC range using the measured values here, you would get an error.?I need to test these things, so I leave this post. removed all existing sources related to frequency tune.?And i applied threshold, weight about speed, and steps. The problem of changing the frequency at the moment of catching the knob has probably disappeared. when the threshold has been exceeded, start frequency changing,?i added some logic to prevent the thresholds from becoming unnatural. If you want to fine-tune, slowly turn it and the threshold will be applied continuously and change very slowly. The tune steps you can select now are 10, 20, 50, 100, 200, but you can change them in uBITX Manager 0.31 (now working)
You can change the step by pressing the function key for a long time. If you keep pressing it, Diallock will work.
The ham band movement applied at 0.28 was set to 0.30, so that region1 was set as the default.
Of course, you can change to the previous operation state by pressing the function key in the band select menu for a long time.
And like the 0.28 version, you can set up to 10 frequency bands in uBITX Manager to suit your country or your liking.
Please refer to below for the improvements and how to upload firmware and more detail. The source and compiled firmware can be found in the release below link.
How to upload firmware and use version up to version 0.27
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
|
Re: UBITX Touch Control TFT Display
All valid inputs.
But with the atmega2560 the user has more inputs and output pins then one could ever use.? With the radio all wired I would estimate more than 25 spare pins
Joe
VE1BWV
On Sat, Jan 27, 2018, 11:40 AM Jerry Gaffke via Groups.Io <jgaffke= [email protected]> wrote: I had never heard of , that looks like a good steer.
They have some nice Arduino starter kits.
However, their 2.8" TFT display is not well documented, and burns an awful lot of pins.
Here's a reply to a question up on Amazon:??
? ? ??I just went through all of the pins marked on the board and the code for the support libraries.
? ? ? It appears that the display hogs all of the pins with the exception of the A5 and the serial I/O pins 0 and 1.
? ? ? This pretty much precludes the use of any other peripheral devices using Wire, SPI, or I2C.
? ? ? The SD card uses digital pins 10 through 13, so if you don't need the SD card, you can snip those pins off
? ? ? (and don't include the SD library in your project). Otherwise the options are limited.
Not what I'm looking for.??
I'd prefer a display with just a 4 wire SPI interface, and power and ground.
Recommendations solicited.
Regarding the si5351 PLL chip breakout board, in addition to , there is also and
Hans of qrp-labs is active on this forum, a kit for his board is $7.75
? ??
The others come fully soldered up, which some may prefer.
Jerry, KE7ER
On Fri, Jan 26, 2018 at 06:42 pm, Joe wrote:
Brein,
?
I use the following: HARDWARE
?
DISPLAY?- Optimum size - 2.8inch TFT - I have tried several types and sizes from various companies - hit and miss. some work but poor clarity etc.
?
Having used the?elegoo 2.8 inch? TFT Display with pen - from "amazon"?has resulted in 100 percent working, clear, clean, crisp displays.
I have ordered 4 over time and quality is persistent. Price? around $15.00 shipped.? Best choice
?
?
Arduino Module?: Atmega 2560 - Ebay is cheapest source at less then?$10.00...? Any Atmega 2560 will work..
I have many different company modules and have found they all work great...
?
DDS module -? SI5351??module?(not just the chip)- available from Ebay or Adafruit direct or amazon around $11.00
?
|
I begin the tuning process yaving the two blue pots placed fully clockwise  but when I have it like this i have much more mA when ptt than if it is turned a bit counterclockwise  Is it normal?
|
I have checked that c51 and r70 have continuity on rx and the opposite on tx (when ppt)
i can hear myself on a receiver but no visible output
i have tried several bands. Nothing
i have checked all ( 1 single wire ones) toroids to be correctly soldered
the 3 wire toroids look good too
o see people looked for a relais failure... but i don’t know the pins that have to be checked
qny hint to find out why the power needle is stuck on ny meter?
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Re: IRF510 amplifier failures
Hello Still thinking about IRF510 failures and ways to avoid making smoke..... It seems that there may be two ways to limit current in BITX RF PA stages that use the IRF510 device.? First would be to incorporate a current limiter in the positive voltage supply to the RF PA stage.? Second might be to use current sensing in the RF PA supply line to cause a voltage drop in the MOSFET bias line(s).? In the first instance it should be possible to use another IRF510 or preferably a higher power, MOSFET as a control that limits voltage to the RF PA section if the current exceeds a preset value (usually this would be 2.0 to 3.0 amperes).?
This circuit has not been built or tested by me (too cold in Idaho hamshack in winter). The MOSFET could be an IRF840, or similar.? Option-B? potentially solves another problem, that of low level noise from powered RF PA stage during receive mode.? 
In the second instance we could get by with smaller control devices if we used current sensing in the RF PA power line to turn off bias to the IRF510 device(s).?
This bias control circuit used by .? You could probably do this using 2N3906 transistors.? I like the fact that it includes a warning light/LED.  Arv? K7HKL _._
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Re: IRF510 amplifier failures
Or build the wa2eby amp with two IRF510's in push pull.
Which works great and is pretty much flat through 30mhz
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On Sat, Jan 27, 2018 at 09:53 am, K9HZ wrote:
Well it’s this way.? You can either spend a little more on the transistor (with the nice input characteristics) and design with minimal parts (e.g. one set of broad band impedance matching transformers and bias network) to work over a large frequency range (1-54 MHz)…. Or you use a cheap motor switch like the 510 and live with the gain roll-off from mismatch (large del C / del Freq) with a fixed set of broad band I/O transformers…. OR you spend more $$$ to build band switchable compensation networks to improve the matching (Can be bulky and expensive but not always).? Pay me now of pay me later.? Many commercial SS Amps that cover 1-54 MHz complete still utilize some sort of compensation network in them to cover the large frequency range and it’s not apparent to the user… even with very good RF transistors (sometimes driven by the transformer material).?? All depends on the part.? Best to Simulate from the S params first.? It will tell you a lot.
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#ubitx New I2C/Digital I/O mod & firmware from W0EB/W2CTX
#ubitx
Additional info to what I just posted - I forgot to mention, now that we're using Digital inputs for the CW and PTT functions, this actually freed up 3 analog lines - A6, A7 and the A3 PTT line so you guys that chose to make the I2C modifications and Digital I/O mods for the CW and PTT inputs, you have your means to implement your S meter, Power and SWR metering.
Oh and I didn't mention that using the I2C bus for the display allows us to use larger standard displays. We've tested one of my 2 uBITX rigs with a 4 X 20 display using the same cheap I2C controller and just a slight software modification to take advantage of the larger display.
The only problem I have with that is the extruded aluminum box front panel layout I chose for the standard display would have to be severely modified to provide room for the large display.
I have a third uBITX coming (they say shipment in about 2 weeks) and I'll put that one into a much larger metal enclosure so I can use the bigger displays.
Jim Sheldon, W0EB
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#ubitx New I2C/Digital I/O mod & firmware from W0EB/W2CTX
#ubitx
Ever since we first released the code using analog line A7 (the so called "spare") as the keyer paddle "dash" connection, I've received a number of comments privately and one or two public ones saying that the A7 was RESERVED for "S" and "Power" metering and we shouldn't have used it. Well rather than make me mad, these "negative" comments along with a lot of information from another close friend who had been researching it, the entire direction of our efforts changed.
We decided that since the I2C communication bus was already implemented on the Raduino card to control the Si5351A clock generator/VFO, and it WAS accessible on the back of the card via the Arduino Nano mounting pins that were left full length when they were soldered to the Raduino originally (at least on mine they were).
I hinted about the possibility of using I2C for the display and immediately several persons cautioned against this because of "NOISE" bursts in the receiver. Not easily swayed and having 2 uBITX transceivers on the desk to work with, I said the heck with it and dove into it with both feet. Picking off the I2C, Power & Ground for an I2C display controller that could coexist with the 3.3 volts the Si5351 uses on the bus to communicate with the Nano was relatively easy. While I was working on the hardware, Ron - W2CTX worked on the initial software and it wasn't long before I had some controller modules in from Amazon that ran on 5 volts. They use the PCF8574 chip. On the Amazon supplied boards, the open drain outputs of the PCF8574 were pulled up to +5 volts by a pair of 4.7K resistors. This would have destroyed or at least severely damaged the 5351 so we removed those 2 resistors and now, the 3.3 volts on the bus via the pullups in the 5351 itself were sufficient to allow the PCF8574 to communicate with the Nano and a standard 2 X 16 display while power the display from the 5 volts on the Raduino like the original display was in the first place so we didn't add much extra load to the on board 7805 (put a 47 ohm 2 watt resistor in series with the 7805's input and you'll amost halve the generated heat).
Once I had the first version of the software in from Ron and had completed the I2C connections to the Raduino, I unplugged the old display from the Raduino and cabled up a prepared display with the modified I2C controller (removed resistors), fired it up and Hello! Once the contrast was set, it looked just like the old display did. I plugged in a pair of headphones and with all the stuff just hanging out of the box, started tuning. I found absolutely NO noise bursts associated with the I2C operation. (I do use a solid power supply that doesn't sag under a load - should be 5 amps or greater).
Okay, with that working, here were 6 completely unused DIGITAL I/O lines so Ron and I decided on using D8 for the paddle dot input, D9 for the Dash and as an afterthought and easier to code - D10 for the hand key --
now comes the sneaky part. Since we don't key CW when in SSB mode and we don't use Push to Talk when in CW mode, he co-opted D10 for both "Hand Key" and "External Keyer" plus in SSB mode as the Push To Talk line. SMOC! (simple matter of coding). Though a separate key jack is probably the best, one could rewire a hand key to use the "Ring" terminal (PTT) of the mic connector to hook it up and in an emergency you could even key the rig in CW using the PTT switch on the microphone.
I've written a DIY manual on picking off the I2C bus, how to hook up a display and how to wire up the now free Digital I/O pins for CW and a complete new manual for the included software all in the attached zipfile.
Disclaimer - You need to be willing to perform surgery on the Raduino card and all the input jacks safely in order to use this software. It WILL NOT WORK unless you make the mods first. A readme.txt file, 2 pdf manuals and a directory containing the program sketch are included in the attached zip.
Use them at your own risk.
73, Jim Sheldon - W0EB with Ron Pfeiffer - W2CTX
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Re: My ubitx Finally shipped
The ubitx I ordered on Dec 14th shipped yesterday according to the email I just got from paypal.
Let the adventure begin..I had added DHL shipping so I will keep you posted..
Brian K9WIS
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Re: IRF510 amplifier failures
Well it’s this way.? You can either spend a little more on the transistor (with the nice input characteristics) and design with minimal parts (e.g. one set of broad band impedance matching transformers and bias network) to work over a large frequency range (1-54 MHz)…. Or you use a cheap motor switch like the 510 and live with the gain roll-off from mismatch (large del C / del Freq) with a fixed set of broad band I/O transformers…. OR you spend more $$$ to build band switchable compensation networks to improve the matching (Can be bulky and expensive but not always).? Pay me now of pay me later.? Many commercial SS Amps that cover 1-54 MHz complete still utilize some sort of compensation network in them to cover the large frequency range and it’s not apparent to the user… even with very good RF transistors (sometimes driven by the transformer material).?? All depends on the part.? Best to Simulate from the S params first.? It will tell you a lot. ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: Like us on Facebook! ? ? email:? bill@... ?
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From: [email protected] [mailto:[email protected]] On Behalf Of philip yates
Sent: Saturday, January 27, 2018 10:17 AM
To: [email protected]
Subject: Re: [BITX20] IRF510 amplifier failures ? So if they are " real RF transistors" probably worth the extra then ? ? On Sat, Jan 27, 2018 at 1:36 PM, K9HZ <bill@...> wrote: I don’t think it’s so much a matter of if they will work or not.? Both will work fine at 50 MHz (and above actually)… the issue is that the RD15HVF1 is a little flatter across the spectrum and from that perspective easier to design around and match.? I use them all the time and they are very easy parts to make work.? A pair will easily put out 30 watts 1-54 MHz if the rest of the design is correct. ? I’ve been thinking about and have had requests for a nice linear amplifier for the uBITx and these parts are cheap enough to use for that purpose too.? I originally designed one using two RD70HVF1 parts but the cheapest I’ve found them is $18 each.? Not a show stopper but the little brothers are cheaper.? If The parts were under $15 in large quantity, it would be a no brainer.? The auto tuner must be finished first though.? Oh, did I mention, the RD series devices are real RF transistors? ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: Like us on Facebook! ? ? email:? bill@... ? From: [email protected] [mailto:[email protected]] On Behalf Of Lawrence Galea
Sent: Saturday, January 27, 2018 3:34 AM ? I was thinking about the RD15HVF1 so that it would be easier for people who want to try 50MHz and perhaps 70MHs where available with suitable mods to the μbitx. The RD16HHF1 appears to be? used in the Ukraine transverters as a PA in the 50MHz, 70MHz and 144 MHz transverters while the RD15HBF1 appears to be used in the 222MHz and 432MHz transverters.? I have the 50MHz and 70MHz transverters and they do work.
Two years ago I worked more than 40 stations on 70MHz (see my log on QRZ dot com) with a simple dipole at about 4M high on the roof fed with some 50 feet of RG58 coax. Last year I built a 5 element LFA Yagi for 70MHz but didn't have time to get on the air.? ? On Sat, Jan 27, 2018 at 3:41 AM, James Lawrie <lawriejk@...> wrote: Hello, That’s why I bought 10 ea... for the uBitxs I’ll probably get the others rated at over 30 MHz. Always nice to stock up on useful parts. Out of all listed on there website what would you recommend for HF/VHF use?
On Jan 26, 2018, at 19:56, K9HZ <bill@...> wrote:
The RD15HVF1 has a bit of a flatter input capacitance curve with frequency so its easier to keep constant gain over 1-54 MHz… but the RD16HHF1 is certainly a worthy part too.? Oh, did I mention, they are both real RF transistors? ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: Like us on Facebook! ? ? email:? bill@... ? ? On same site I found these, made for 30 MHz?RD16HHF1. Sooo I bought 10 of them, plan to try in Bix40 first. Data sheet even shows a reference amp design, and they are 12 volt like the other one. If it works I’ll let everyone know. ?
On Jan 26, 2018, at 11:32, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
The RD15HVF1's should be operated at not much more than 12v.
At 12v, the IRF510's would survive just fine with no antenna connected.
That's an infinite VSWR.
So not obvious that this is a solution to blown FET's.
Though I do think the the Ids curves go up more slowly as Vgs increases on the RD15HF1's,
which makes RV2,RV3 not so touchy.
And the RD15HF1's might be easier to drive at 30mhz.
If you do swap them in, let us know how much power you get at 30mhz.
Jerry, KE7ER
On Fri, Jan 26, 2018 at 03:54 am, KD8CGH wrote: Wouldn't it be better to change to a RD15HVF1 for high VSWR
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Jim Sheldon
Bob Benedict, KD8CGH
K9HZ