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Showing posts from December, 2016

Bitx40 Project ~ So you want to build a Bitx40?

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Building the Bitx40 ~ The how to for the newcomer!12/31/2016 ~ Life is Too Short for QRP! So Ok guy's here is how to boost your signal (using an external linear amp)  so you can be heard and duck those dreaded repeats of your name and QTH.

 It is pretty simple to implement. All you need is three diodes if you include the 1N4148 snubber diode across the reed relay coil, a RCA phone jack and a terminal strip. One side of the relay contact is simply grounded by soldering to the PC board that holds the reed relay (yep super glued upside down to a scrap piece of PC Board). The other lead goes to the rear panel mounted RCA jack. The two 1N4007 isolate the circuits from each other. With this arrangement I am able to drive my SB200 to 100 watts output. Pretty cool.

73's
Pete N6QW




73's
Pete N6QW

About a month ago I agreed to give a Skype presentation to a local ham club known as the Ventura County Amateur Radio Club (VCARC) on the subject of homebrewing. Hey I am really good at s…

The Bitx40 Project

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The Bitx40 Project --a good rig for just a few dollars!12/28/2016 ~ First QSO on the new Bitx40. Now at Four Contacts Total! Listen to the 1st QSO on my new Bitx40. Click the link below. General impressions are that it is a good value for $45 but get the digital VFO add on for another $14. Now that a successful build has been achieved time to move on to another project. Oh for the microphone enclosure (seeing as the electret cartridge is included) I took a defunct microphone and adapted it to the simple cartridge. It seems to work OK. I missed my by Christmas QSO goal by a couple of days but it is working none the less.

Found out why you need the coupling cap out of the DDS! Initially I was advised to disconnect L4 from the pin header. Don't do that! Leave everything as built. The reason I needed a blocking cap was that the hot side of the Pin Header goes right into the base --any RF signal must have the blocking cap. In VU2ESE's Digi VFO there are blocking caps coming off of…

FPM5 ~ Using Diagnostic Tools

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FPM5 ~ How to save from pulling out your hair!12/27/2016 ~ Revised Simulation This is the value of LT Spice as you can modify the design without soldering one wire. Many options and iterations can be evaluated and the bonus --it can be done quickly. In chasing the elusive problem of too much gain at lower frequencies and not enough on the higher bands, I am being convinced that it now is not the specific circuit I thought the problem. But at the same time there is an opportunity to optimize that circuit. So that is what I did at 4:30 AM this morning. My daylight hours are taken up with caregiver duties so I have found working in the early morning hours does provide some opportunity. I am trading sleep for ham radio design work. Noteworthy in the new design is forcing the impedance matching by going back to the original primary winding (8 turns) and changing the secondary to two turns. The matching is now 64/4 so that it is a 16 to 1 transformation. The secondary is terminated in 50 oh…

A Diversion from Radio Projects

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The FPM5 is in the box but has a few issues. You know the drill: Worked great 'al fresco" but now that it has been made neat there are some RF feedback issues! Sometimes it is good to take a break and just do something else.[See video of FPM5 at the bottom of the section 12/23/2016.] So here is the something else. My sister whose OM is also a ham sent me an early Christmas present and I must admit it has really captured my attention. By way of history I was born in a small town in western Pennsylvania (PA) not far from the city of Pittsburgh. The name of the town was New Kensington. While PA was known for coal and steel it was also home to aluminum manufacturing which of course was in New Kensington. Yes those Alcoa pots and pans were at one time made right there. The Alcoa Research Labs were also located there. Much of the area economy was derived from those working at Alcoa. So the book I received is about New Kensington history but a different side of the economy. After al…

FPM5 Wiring Virtually Complete ~ Smoke Test is Complete!

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Wiring is 99% Complete!Smoke Test Passed!!!! Late Breaking News.



The only remaining wiring is to connect the circuitry so that when you hit the PTT or place the rig in TUNE, the Color TFT displays "ON THE AIR". How cool is that? There are two photos of the rear deck area one has the shield over the PA and the last one has the cover in place. Stay Tuned for the Smoke Test Possibly on 12/16/2016. The wiring mess has now been better organized!









This has been about a four month journey and I have learned a lot. 73's Pete N6QW  

The Bitx40 Project ~Multi-Tasking at Work

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Working Two Projects (FPM5 & Bitx40) Simultaneously!
As I wire up the final configuration of the FPM5 I am also working on building the Bitx40. Mind you this is being done under severe time constraints associated with my caregiver duties. So indeed it is a high wire balancing act. There is frustration in being able to only accomplish so much in short blocks of time. But in some ways this is not all bad as it forces you to time manage and to "noodle" what are the most efficient ways of doing the hardware tasks. Just so you know here are  update photos of the final wiring status of the FPM5. Keep in mind the rig was purposefully built in modules and this pays off "big time" in that I am able to easily remove modules and this facilitates the wiring process. It still looks like a jumbled mess -- but it is an organized mess. After about a day of intermittent work the above now looks like below. Still a mess but getting better! Yes I have installed "my version&…

FPM5 ~ Reverse Polarity Protection

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FPM5 ~ Protecting All of the Hard Work One of the sickest feeling you can have is to plug in a new rig to 12 VDC and watch it go up in smoke as you realize you had the leads to the power supply reversed. yes I have done it and I am sure you have too. In the SolderSmoke Podcast #191 Bill, N2CQR and I were talking about this subject specifically in regard to the new Farhan, VU2ESE's rig the Bitx40. Bill having one strongly encouraged the addition of reverse polarity protection using a diode. Of course as usual any time you make a suggestion you get the naysayers who lurk the various reflectors whose sole goal in life is to spread negativity about anything. Typically these individuals have never built ANYTHING and think they are experts! They are often quick to pan a solution and they quickly jumped on Bill! I am facing the same situation with my FPM5. Man I have months invested in this rig and the last thing I want to see is it smoking from wrong polarity being applied. But I wante…

FPM5 -- Coming Down the Homestretch!

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FPM5 ~ The Final Assembly is on the Threshold!December 8, 2016 ~ TRGHS (The radio Gods have spoken) Something weird happened today! At about 10:00 AM two boxes showed up at my door step. One was the wire needed for wiring up the FPM5 plus a couple of 8X2 LCD's and some other  parts. Now I can get started in earnest with the final wiring phase of the FPM5. The second box was addressed to me complete with my call sign and the return address was from a person in New Mexico. That seemed strange as I hadn't purchased anything not even on eBay. So I open the box and contained therein are three rolls of solder. Hey cool something I can use --I am burning lots of solder these days. But I was mystified. Then I had a TRGHS moment and realized what was going on. Several weeks ago I checked into the Albuquerque Boat Anchor Net. The check in process involves identifying your station and what sort of boat anchor gear you are running. I could hardly contain myself as I explained that the …