QRP - Log:   Updates To Permanent Content


Click on the Junk Box page for my latest blog update. I delete most Junk Box page content over time.

April 14, 2013 —  I added Section 3:  50 Ω MMIC Bench Amplifer to the VHF 2013 Veronica web page.

March 31, 2013 —  I started a new a new content page called Pin Outs

March 25, 2013 —  Section 9: an essay about the 1981 Progressive Receiver, plus the final section — 10: Miscellaneous Pictures and Figures added to Sundry 2012-13

March 18, 2013 —  Section 8. Popcorn AF Amplifier for Receivers — Reprise added to Sundry 2012-13

March 10, 2013 —  I added a new VHF content page for 2013: VHF-2013 - Veronica

February 16, 2012 —  I added Section 7  -- A Journey Above HF --  to the Sundry Experiments 2012-13 web page.

February 14, 2012 —  I added Section 6  -- Non-Mechanical Iambic Paddle -- to the Sundry 2012-13 web page.

February 1, 2013 —  A seperate QRP—POSDATA added to RF Workbench 4. Now QRP— POSDATA 1, 2 and 3.

December 15, 2012 —  I added Section 4 to Sundry Experiments 2012 - 2013 . A PLL circuit from EMRFD.

January 5, 2013 —  I added Section 5 to Sundry Experiments 2012 - 2013 . A simple AF feedback amp.  An essay concerning L-C meters was also added on RF Workbench 5.  Section 5.

December 22, 2012 —  I deleted the web page Tuning VFOs with a PN Junction since some of the experiments were poor quality and performed back in 1998 when I was more ignorant than now. I've learned much since then and my new VCOs from the past 1-2 years reflect this knowledge. The Selected QRP Reading list and Cascode 7 Receiver web pages were also wiped.

December 15, 2012 —  I added Section 4 to Sundry Experiments 2012 - 2013 . A PLL circuit from EMRFD.

December 3, 2012 —  I added Section 3 to Sundry Experiments 2012 - 2013 . Interview with Jason from Etherkit

November 13, 2012 —  QRP — Posdata added to the VHF to the Max web page.  Section 5: Z-Comm VCO.

November 1, 2012 — Sundry Experiments 2012 - 2013 web page added. 
QRP — PosData added to Section 2 of  Power Meter Calibrators on RF Workbench 5 and updated again on Nov 22, 2012.

October 16, 2012 —  VHF FM web page officially added. Already, it has spawned a first supplemental web page

Sept 24, 2012 —  QRP — Posdata added to the end of the HF Ragbag web page. I added a bypass and decouple network for HF to lower VHF.

August 17, 2012 —  QRP — Posdata #2 added to bottom of the Receiver Band-pass Filters web page.

August 6, 2012 —  Section 5: Some Experiments with RF Bypass Capacitors added to the HF Ragbag web page. Also a new QRP — Posdata added to the bottom of the Crystal Parameter Checker web page.

August 1, 2012 —  QRP — Posdata added to the Receiver Band-pass Filters web page.

July 12, 2012 —  I added a corrected schematic on the Wee Willy page: Wayne. M0WAY — 14 MHz PA under August 25, 2011.  Also, added a new essay on Microphonics in DC Receivers. See Section 4 on the HF Ragbag Page

June 23, 2012 —  RF Workbench 5 added. Click here.

May 31, 2012 —  Galina discovered that I neglected to publish the proper version of the Hobby and Fun 2011 page and corrected my error. A fine-tuneable Wien Bridge Oscillator idea from Ken Kuhn now appears at the page bottom.

April 21, 2012 —  I heavily edited RF Workbench 1 and 2.

April 13, 2012 — Web site purge. I removed RF Filters, VFO 1998, QRP Workshop Ideas, Miscellaneous Schematics and Photos, Base-biased VFO, Funster Transceiver, Miscellaneous Circuits and Ideas 2005 and Crystal Oscillator Offsets. Reason: substandard.

April 6, 2012 — 50 MHz Receiver Pre-amp and Filter added to VHF to the Max web page .Section 4.

March 26, 2012 —  HF Ragbag web page added to top-level menu. Non-VHF experiment repository for 2012.

March 19, 2012 —  VHF to the Max web page added to top-level menu. 50 MHz VCO experiments added to this page in Section 3.

March 14, 2012 —  EMRFD review edited.

February 29, 2012 — Minor edits to the Audio Transistor Input Impedance Experiments web page. Also, I updated the calculation of the common emiiter amplifier base input resistance using the better formula: Rin = (B+1)*(re + RE') [while ignoring REB]. This is my favorite web page on the site.

February 26, 2012 — QRP— Posdata added to the bottom of the 2nd NDB web page

February 17, 2012 — I introduced a new miscellaneous VHF page: VHF to the Max — I'll slowly add stuff over 2012.  Major editing done to the Broadband Transformer web page.

February 4, 2012 — RF Workbench 1 and 2 significantly edited. 2 new photos added.

January 28, 2012 — QRP — Posdata added to Crystal Parameter Checker web page and to QRP Modules 2011 under 7 MHz VCO Experiments on this web page. I re-wrote the temperature compensation section of the VFO-2011 web page and added 3 photographs.

January 3, 2012 — Web site change: I update web essays with an "epilogue section". In 2012 and on, they will be called QRP — Posdata (Spanish for post-script or epilogue). Posdata #2 added to the RF Workbench 4 web page.

December 17, 2011 — The Butler Did It ! - First VHF Experiments 2011 web page added. A 50 MHz frequency doubler added Dec 26, 2011.

Nov 12, 2011 — Our server went down for 16 hours. Both AC power and cable Internet to the warehouse failed after a rain storm and wind gusts knocked down some trees that severed the hydro and cable wires. Expect more weather-related down time as Winter approaches.

Oct 15, 2011 — VFO-2011 added.

Oct 2, 2011 — RF Workbench Page 4 added.  On Oct 17, 2011 I added an epilogue.

Sept 20, 2011 — Double Stacked Toroid VFO 2008 web page pulled off. It was substandard and some of the material will re-emerge on a VFO 2011 page this Winter.

Sept 19, 2011 — I updated the SWL essay since it was 6 years old and much has changed with respect to Internet radio. Over time I have received ++ emails expressing different views. I am more a SWL than a Ham and offer just 1 opinion and live by a "each to his own" mantra. Context is everything - this is a radio electronic experimenters site that recognizes SWL'ers are important members of the radio community. Click.  Wee Willy web page updated again!

Sept 12, 2011 — Design Center concerning popcorn receiver band-pass filters added. Click.

Aug 26, 2011 — Minor update at the end of Wee Willy DSB transceiver. New Junk Box Blog format. Change is good.

July 30, 2011 —  New web page QRP Modules listed on the main menu. Currently under construction.

March 31, 2011 — 2 photos added to the Ugly Construction web page

March 19, 2011 — New content; Hobby and Fun 2011 . I'll slowly add more stuff over the year.

Feb 12, 2011 — New content. Miscellaneous RF Experiments 2011

Dec 29, 2010 — New content. RF Workbench Page 3

Dec 12, 2010 — Final additions to the the 2010 Hobbyist Page added — these concern matching FETs, BJTS and diodes.

Nov 10, 2010 — Some editing and 2 photos added to RF Workbench page 2.

Oct 9, 2010 — This October marks the 12th season of experiments for the site. I have 4 partially completed web pages on the go — pure craziness. I decided to finish them 1 at a time and then add them sequentially. Today, a new web page was added and is 1 of 2 supplements to a future main QRP audio page:  Audio Transistor Input Impedance Experiments. The first new "permanent" content since March 2010.

Oct 7, 2010 —The Junk box page lay out was simplified:  Accommodating the various modern Web devices plus screen resolutions proved difficult with the old html code. Although less impressive, the new format updates quickly and looks the same on every computer.

Aug 15, 2010 — The cable supplying the Internet connection failed. The site went down for 25 hours. Expect more shut downs over the next couple of days as we resolve any remaining problems.

August 6, 2010 —  I decommissioned the historic home page URL http://www.qrp.pops.net/default.htm. This page was a html hard-coded parallel version of the the correct home page URL http://www.qrp.pops.net. It was just too much work to continue to update the old (pre-2006) home page in addition to the proper home page.

June 28, 2010 — Web subtitle change : Amateur Radio Electronic Design to shorten the name and reflect the site's main purpose.

Effective May 17, 2010 — Schematics now use the 16-bit png format. I have abandoned the 8-bit gif format

May and June 2010: The pops.net net control crew rest up for the next big wind storm. The servers lost power for many hours on May 4 and June 12 due to bad weather. Severe storms arising from the Pacific Ocean threaten our AC power lines each Spring.

March 2010

  1. Wide Range L-C Oscillator added to Hobbyist 2010 page. Link  March 7
  2. JavaScript Applet K added to the QRP Tools page March 11
  3. RF Workbench Page 2 added. Link  March 15

February 2010

  1. JavaScript Applet J added to the QRP Tools page Feb 6
  2. Editing of the Low Noise Crystal Oscillator web page Feb 22
  3. RF Workbench Page 1 added. Link  Feb 18

January 2010

  1. Experiment #6 added to the Hobbyist page Jan 2
  2. New content Low Noise Crystal Oscillator Jan 10
  3. 2 photos added to the bottom of the Ugly Construction web page. Jan 12
  4. 1 photo added to the Broadband Transformers page Jan 12
  5. New content Hobbyist Page 2010 Jan 13
  6. New content: Supplement to JavaScript Applet G which is located on the QRP Tools page Jan 11
  7. Additions to the Low Noise Crystal Osc page: the DSO versus CRO essay, plus 5 MHz crystal oscillator added Jan 31
  8. JavaScript Applets H and I added to the QRP Tools web page Jan 31

December 2009

  1. It has been brought to my attention that the email replies I am sending are not compatible with some of the latest email software such as Thunderbird etc. The reason was that I was using a homebrew email program written over 10 years ago. It is now obsolete. A new email platform is now in place along with a completely new email address. Consult the email web page for more information. Dec 30
  2. Experiment #5 added to the Hobbyist page  FAQ updated and edited. Dec 30
  3. Experiment #4 added to the Hobbyist page Dec 26
  4. Experiment #3 added to the Hobbyist page Dec 23
  5. What does the output of a diode ring mixer look like in your oscilloscope? This has become a FAQ. The question is answered in a contribution by Wes, W7ZOI. Big thanks to Wes for this content. Dec 22
  6. I am very pleased to present the Mike, KL7R Memorial Receiver Experiments. Click here  Dec 19
  7. New bulleted list format added to this page to improve readability Dec 19
  8. A minor addition was added to the bottom of the Ugly Construction web page. Flux pen photo and text. Dec 19
  9. Minor updates to the VFO 2008 "Stacked Toroids" web page under Epilogue - December 19, 2009
  10. Update to JavaScript applet Item E: Calculate Cut off Frequency for an RC Low Pass Filter. Now has a capacitor range from 0.1 nF to 1500 nF. QRP tools page. Dec 19
  11. Editing plus a photo added to the broadband transformer page. This page was improved to support an upcoming project. Dec 17
  12. Drafting errors on this schematic corrected (fuse position+ negative rail LED polarity). From this web page. Thanks to Paul, K0EET and Tom for the good eyes and their emails. Dec 16
  13. VFO Experiments 2009 updated again; 3 images added. Supplemental web page added and updated Dec 13
  14. New JavaScript applet added to QRP Tools page; Item F: dBm calculator. Dec 12

Nov 22-27, 2009

1 Hertz Precision Time Base added to the Hobbyist Page.
VFO Experiments 2009 added
The top level menu item "Java Tools" was renamed QRP Tools. This menu provides a link to my Webmaster's page and some basic JavaScript applets. Some new material will appear on the Junk Box page during this time.

Nov 20, 2009

Finally; Fall-Winter experiments begin. A small update on the VFO 2008 web page under A 3.5 MHz VFO for Diode Ring Mixers was added.
The RF Preamp page was updated with some content  that was first presented on the Junk Box web page. I have received a lot of email about these amps and decided to permanently add them to the site.
The W7ZOI file linked on this page is now in pdf format.

Nov 1, 2009

The Ugly Construction web page was augmented and re-written. 2 new photos were added. This term actually came from Wes and Roger Hayward.
A new Electronic Hobbyist page was added to the drop down 2009 menu.

Oct 25, 2009

Some small updates to the Junk Box page were made. I don't ever think I have been so excited about upcoming Fall and Winter experiments as there are a number of cool, new ideas in my notebook. Extra work and travelling have kept me off the bench, but this will cease in mid November. After that, it's back to the work bench. The Fall-Winter experiments will include some HAM, SWL, general electronics and tube guitar amp experiments. Thanks for your feedback and ideas!

Oct 19, 2009

RSS feed. Click on the orange RSS icon above to establish a feed. I will only show 1 item; the latest addition of major new content to the site. Additions to the Junk Box page will occasionally be counted as "new content" and will be included on the feed.

Can anyone guess what brand of beer is in the tool box ?  Yes.... its

Oct 12, 2009

Fall weather has come to Western North America! Thanks to Cor, PA3COR for debugging the JavaScript code on this page.  Apps number D and E now work in Firefox. Rediscover the fun and learning of scratch homebrew electronics!


Coilguy