KE5HPY Builds a QRP Transmitter

 

FB Chuck, very cool.  Please send us more reports on this rig.  

Chuck has been on the blog many times, with many projects: 

https://soldersmoke.blogspot.com/search?q=KE5HPY

73  Bill 

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Bill/Pete:

 

Thought you would appreciate a recent project inspired by the fabulous EMRFD.  This started as a test bed W7ZOI universal tx to evaluate my stock of RF BJTs and employ some FT-243s in the shack.  That was interesting by itself but the 16-32 dBm output (choice of device really matters!) did not reach the intended targets using my 40m dipole.  So, add a W7EL RF PA and a nifty, clean 7W emerges after damping output from Q2.  The final is pleasantly efficient and needs only a modest heatsink to survive key down for 60 seconds.  KFS then reported S7-9.  Success.  Time to box it up and go XTO, add a meter output at 30dB down and an RF driven LED indicator.  Left room to add an ATtiny85 CQ keyer but ran out of time.  Had to move house and knock down my 40-6m antennas.  That was the most painful part of moving.  So this rig sits while I find a new place to hang antennas.  Eventually, the TX will get a RX mate when it is possible to box up a 40m DC RX with Si5751 and OLED display. Am still trying to solve how to mount an OLED display cleanly in an aluminum box. First, I have to reconstruct my workbench.

 

Keep up your good work, and that is no April Fool’s joke. 

 

73,

 

Chuck KE5HPY

The New Display: The PHOLED

 

At first I thought, "faux-OLED"?    Then I thought, maybe an OLED from Vietnam (like the delicious soup)?  No, that was not it.  But this IEEE article explains how new blue phosphorescent materials fix OLED display weaknesses: 

https://spectrum.ieee.org/blue-pholed

Shuji Nakamura -- The Inventor of Juliano Blue LEDs

He is the 2014 winner of the Nobel Prize for Physics.   He is the person who figured out how to make blue light LEDs through the use of an Indium Gallium Nitride semiconductor.  I was reading about him this morning in "Conquering the Electron" by Derek Cheung and Eric Brach.  Thanks to Nakamura, the numerals on all my frequency displays glow in a pleasing Juliano blue.  Three cheers for Nakamura! 

More on him here: 

https://www.trumpf.com/en_US/presse/online-magazine/nobel-price-winner-nakamura-wants-more-light/

Organic Electronics

This made me think of the OLED screens.  But they are not, as far as I know, gluten-free. 

This guy would probably be a QRPer, probably running an HW-8 off solar panels. 

SolderSmoke Podcast 199 Eclipse, Regen, BITX, DC RX, 3D OLEDS, Iphone Boxes, Mailbag

SolderSmoke Podcast #199 is available. 

http://soldersmoke.com/soldersmoke199.mp3

2 September 2017

The Eclipse.  The Floods. 

Sawdust Regen gets John Henry off to a good start. 
Voltage regulators as audio amplifiers

The return of the Simple-ceiver (Direct Conversion)

Ceramic Resonators

3D OLEDS

iPhone Boxes as rig enclosures

Electric Radio on Frank Jones

17 Meter Contacts 

MAILBAG

ZL2CTM's Homebrew Transceiver Project

Wow, Charlie has a lot of very cool ideas in this initial video.   Some suggestions: 

-- With the IRF-510 in the final, beef up the heatsink, and follow Farhan's lead by including an option for 24 volts on the drain.  That would take you  up to 20 watts or so (for those who are so inclined). 

-- Could that Teensy SDR board work at the IF frequency?  If so, consider putting it ahead of the crystal filter.  This would enable us all to join the Waterfall Signal Purity Police Force. 

-- I love the OLEDs too, but I found them to be noisy.  I minimized the noise with shielding around the OLED and active decoupling on the power line to the AF amplifiers.

More of Charlie's work here: 

https://plus.google.com/107506245856154702088

Real-Time 3D on an OLED Display

Oh man, I thought I was so cool when I got the OLED to display 7215 kHz and other frequencies.  Then I see this.  What next?  Real-time 3D SDR Waterfalls?  On an OLED?  Holograms?  

From: 
http://hackaday.com/2017/08/08/atmega328-3d/#more-267887

AC9JQ's Mini Digi VFO/BFO Al Fresco with OLED (and noise test)

From Dean AC9JQ:

Just completed the VFO/BFO/Arduino/OLED module for my radio.  I also have the LPF, BPF and crystal filters completed and tested.  Next will be the audio amplifier and NE602 modules.  I will probably build one of the NE602 modules and test things out as a DC receiver.  My ultimate plan is to have the rig no more that 1"x3.5"x3".  I still have a lot of "stuff" to stuff into that size of box.  I'll keep you posted.


I have been able to contain the entire Arduino/Si5351/OLED into a small cube in the front.  The rest of the radio has to fit on two levels in the rest of the area behind the Arduino/Si5351/OLED.  I think I will build the audio section and on NE602 mixer and run it as a direct conversion first to vet out any noise or other problems.  Bill, that small coax that you pointed out will really help on this build.  I used a small piece as a power feed-thru and will use it to feed out the VFO/BFO signals, thanks again for that pointer.

I decided to test for noise on the TIA transceiver test bed.  See the video of the results.  Not too much noise.  I'm only using my indoor magnetic loop for an antenna.  Video is kind of sloppy, but taking off the antenna and turning up the volume shows how little noise is left in the system.  Now time to stuff the rest of the radio into the tight quarters.

https://youtu.be/kXf7-7FtxEU

I purchased OLED from ebay.......

http://www.ebay.com/itm/401234789687?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

0.91'' 128x32 IIC I2C Blue OLED LCD Display DIY Module DC3.3V 5V For PIC Arduino | eBay www.ebay.com IIC interface. OLED display, no need backlight, self-illumination, the display performance is better than the traditional LCD display, also lower consumption. VCC: Power (DC 3.3 ~5v). Display Color:Blue. | eBay!

They are nice and compact, although as time goes on, I'm sure they will be harder to read.  I'm hoping to have an alfresco version in a week or two.  I used much of Pete's code from the shirt pocket transceiver upgrade, modified the code to address the smaller display and add USB/LSB capabilities. 

73's  Dean AC9JQ