30m Crystals Arrived

As promised, my previously ordered 30m Crystals arrived today - now I am ready for more 30m projects.

SMD - Without Solder Mask

The last few days I have been soldering several of my Home Brew (HB) PCB's and playing with several different ideas for the best method of mounting SMD parts. My projects do not have the funds for proper solder mask.

I have tried loading the board with components on solder paste. The solder paste that I use is intended for stencil application - which I have found, if thined with a solvent, works very well when applied with a blunt round tooth pick. Parts are easy to place and stay in place. The PCB.s that I tried was very dense and because it is HB, I did not have a solder mask to help prevent parts from moving a little when re-flow in a toaster oven. On one occasion, two adjacent parts  floated to join at one end, at it turns out the two ends had a small trace between the pads, but it was enough for the solder to flow to each other. A production solder mask would have prevented this movement.

Also, I tied using a small iron with solder pasted parts, because of the density, I have several SMD 1206 parts with a trace between pads. Pressing the parts into the paste squished the paste under the part and that provides a potential short to the trace under the parts. Most of those parts had to be re-fitted. Lesson learned, be extra careful with parts placed over traces - avoid it if you can.

I have tried, and like direct soldered SMD's, which works well for me. I suggest several things;

• Just before installing parts, clean and polish the board as normal, then rub a thin layer of "Flux" over the board, it is a bit messy but it can be cleaned up later. Solder acceptance if much faster and stays cleaner while installing parts. Clean solder does NOT drag when releasing the iron from the pad - resulting in fewer bad joints or shorts.
  

• I suggest, for a new parts, 

1. Tin ONLY the first pad.
2. Place the part on the pads, one end will be setting on the solder mound from step 1.
3. Hold the part down gently with a tooth pick.
4. Heat the first pad with a small soldering iron.
5. Allow the part to drop onto the pad as the solder melts.
6. Do not try to add more solder - that will be done later and only if necessary.
7. Do NOT solder the other pad, for now.
8. Repeat for a group of  SMD parts.

• I like the idea of have a second chance to look at the newly installed parts, one last time before committing to a double ended soldered part.  
  

• Note: Once a part is soldered on both ends, and if it needs to be moved/removed/replaced - it is the same as a board repair, which is never as clean or easy as a new part installation. Removing a part with only one pin soldered is very easy.
  

• I found that small diameter 62/36/2 Rosin-Core Solder works much better than most other solders that I have used (available from Radio Shack on small spools) - the 2% silver makes for very smooth and shiny joints. Note: I have NOT found another source for this type of solder, a friend, Wayne McFee NB6M put me onto this - thanks Wayne.
  

• If necessary check adjacent traces for solder and solder paste shorts under the parts, they are much easier to find with fewer installed parts.
  

• After inspection, solder the other pad(s) of the SMD parts, then touch up the first end only if necessary - the previously rubbed on Flux make the joint touch up just that much easier.

• After soldering is complete, clean the board and remove the Flux as normal - I don't suggest Acetone - I like to use an Isopropyl Alcohol (99% , from the drug store) bath soak and blow dry, and the maybe followed by  a "Contact Cleaner" as you get some pressure-washer spray action, and it is easy to use. Rosin is an organic flux and Alcohol is an organic solvent.
  

• I use the "Carburetor Cleaner" (from the auto store) to pre clean the PCB before Toner Transfer and for Toner removal after etch - Carburetor Cleaner is Great Stuff.

So far, I have successfully produced several HB PCB's, some with very small 8 mil traces, and I am very very pleased with the results.

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Planning New QRSS and WSPR Projects

I am planning several new 30m QRSS and WSPR projects, availability of the right Crystal is always a major  factor - so, I placed an order with "Expanded Spectrum Systems". They have a good price and ship the same day. For my projects, I need a few 10.140mHz crystals.

The Second New QRSS Grabber Web Server Location

I have moved my QRSS Grabber WEB Server to a new Data Center Location, the URL will stay the same but access to the Internet for users should be more stable. The QRSS Grabber is still running on a system and receiver at my home location and just the images are transfer to remote Data Center and WEB server. Check it out, at:

    http://www.metplx.com/WA0UWH/grabber

All of this seems complicated, but it is due to the fact that my home Internet is served via a Satellite Connection, which does not provide reliable access for users from off site.

Later I will move QRSS receiver to the same location as the WEB Server.

QRSS Project - Update Status

This is an update on my QRSS Project of a previous post - not much to look at. So far, at this stage it is still on the breadboard, but seem to be very promising. It is much more stable than I would have thought considering the current state and temperatures that it has endured. It ran in this configuration for 8 days on one 9 volt battery, until the battery went down to about 2 volts - I forgot to check it's progress.

My goal is to include the modulator and design a PCB for a SMD configuration.

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September 2009 - eBuild-A-Thon and BBQ

The September 2009 eBuild-A-Thon and BBQ has come and gone. Even with some rain and a light turn-out, many projects where worked and discussed.

Richard NoCALL worked on this antique look-a-like radio kit, but was unable to get it to receive. It needs a little more trouble shooting.





Steve KD7YTE worked with his Granddaughter, Annie, to build an AM Broadcast Receiver, with a Snap-Together Kit. We later sent more time erecting an long wire antenna for it, than that spent on the kit itself - but, when finished, it worked well.




Annie was sys-op for the Snap-Together Kit AM Broadcast Receiver. She learned that when wires were inadvertently disconnection, things do not work well - That's, Step One of Ham Radio!

Above, Tess is in the background waiting for Annie to get back to playing ball. Tess just does not understand all of this Radio stuff - especially when there is a perfectly good ball to be played with.




John KC7NVE and I scaned a 4:1 balan with several different types of antenna analysers - which confirmed that the balan is real flat up to 26mHz,  as we had hoped.

John calibrated his 100KHz marker oscillator with WWV, using audio from the receiver fed into the computer for spectrum display - which makes the task very easy.  John had several other projects to show and tell.


Charlie K7KN and I setup WSPR on 30m and received many spots, Charlie is planning to do the same from his QTH (Sorry, no photo taken).

For Demonstration, I demo'd the Laser Toner Transfer Process for creating PCB's. See previous posts. Next time around, Charley wants to build a PCB for a Band Edge Marker for his QRSS and WSPR adventures.

UPDATE: After detailed inspection of the PCB created for the demo, I have noticed two copper bridges on the PCB. If this had NOT been just a quick demo, we would have inspected the Laser Toner Image very closely before etching. I have now, also, reviewed the negative Green print and the two bridges are apparent, therefore the problem would have been easily avoided. With only a little more difficulties, this PCB can be salvaged.

Note: this was not a defect in the Laser Print, it was a small "chad" from the Green Sheet that I should have removed.

One of the Copper Bridges is shown

With the good food, I think fun was had by all - Thanks to my sister Carolyn and Richard NoCALL for help with the food.

My dog Tess, just loved ALL of the attention (Charlie, next time throw a ball for her, you will be her friend for life!).

We finished up just before the Heavy Rain Storm.

Thanks to all - It was great - Eldon WA0UWH


Follow up Email:

---

Eldon et al,

Annie, Richard, and I had great fun at today's eBuild-a-thon. Great location! Great rainy-day eating shelter! Great people! Many thanks to Eldon for hosting this event!

Best regards,

Steven

---

I'd like to send along my appreciation to Eldon for hosting the build-a-thon today. Nice spread Eldon! 22 acres of rolling hills/ranch-land with an 8000 sq ft "workshop" The cattle, alpacas, and donkeys were great to see.

I grew up working in my dad's metal products machine shop, but we didn't have the variety of machines that Eldon has. Most impressive was the vertical milling machine!

After spending about 30 minutes getting a thorough tutorial on WSPR ( by the time I left at 1600 hrs 15 stations were hearing Eldon including Japan on 30 meters 1/4 wave with his copper pipe antenna with no ground radials!) we moved on to lunch.

After lunch, the group followed Eldon from start to finish in creating a printed (surface mount) circuit board. He made the process seem so easy. We saw the schematic on screen as it was converted by two programs to laser printed board design on paper, then transfered again on to copper, through a few more steps to the final product. Very impressive.

Thanks again Eldon. Look forward to October.

Charlie

Link to Charlie's photos: http://picasaweb.google.com/splitsky9/BuildAThonImages

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Eldon,

Thanks again for today's event, to you and Caroline.  I enjoyed meeting you and the guys, had a fun time, and learned some useful things.  You have an excellent setup there at the ranch and it seems like a very nive location.  I hope to see you again next month. Take care, stay healthy.

Rich

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A new Audio Amp for DC Receiver

With my new found abilities of home PCB construction (see previous PCB posts), I have put together the circuit layout for a Audio Amp for my Direct Conversion QRSS Receiver. It has not tested yet, but I am hopeful, . . . (that it does not turn out to be an oscillator?).

 Audio Band Pass Amp using LM324N

Yes, there are four jumpers on the board, plus one under the IC, I did not want to make this a two sided board.

And if you look very close, you can see I forgot one two solder joints on the capacitors to the right of pin 8, and 14.

Forgot Solder Near Pin 8 - This is an Easy Fix!
Note: These are 1210 pads with 1206 parts, also note that there are traces or Ground Plane under many of the parts, it is easy to create solder paste shorts under the parts - as I have found out!

Now for some testing and circuit check out!


UPDATE 1:  Well, . . It is, . . . . an Oscillator! . . . . . I will have to do some more checking on the layout, and maybe some "LTSpice" simulations. Maybe it is just a short, or a miss mounted part - alot more checking is needed.

UPDATE 2:  I think I need to look for another circuit for my "Band Pass" audio amplifier, the circuit that I used was cobbled together without much thought. What I need is about 60-80db of gain with; 200 to 2000Hz Band Pass.

UPDATE 3:   A very old Navy friend of mine, Richard Davis, after seeing the photo, offered this bit of advice on FaceBook: "Don't use Taiwanese electrolytics! ;-)". He must be very observant, as I used the Caps that I had in the junk box. Maybe, I should look at the selection of Caps closer, or maybe the International friends will also have comments.

I found the following Active Band Pass Filter Calculators:

http://www.wa4dsy.net/robot/bandpass-filter-calc

http://www.captain.at/electronics/active-filter/

UPDATE 4:   I found one layout error, the output feedback cap of the third stage op-amp was connected to the bias line and not the the inverting input cap as it should. That would make the op-amp oscillate!

I may change the component values used to implement a 6 pole Chebyshes Filter as the Filter Calculator above suggests, the schematic and layout stays the same (after I fix the layout error found above).

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My QRSS Grabber is Down, AGAIN!

Darn, my QRSS Seattle Grabber Web Server is Down again.

I am having trouble keeping a web server runing in a cheap Internet location. I have one other location that I will try and move the web server, this new location should be more reliable. It will also be a better location to put up an Antenna for the attending QRSS receiver.

The move to the new data center will take place some time this week (9/14).  If all works well, the grabber should be working again late this week.

UPDATE: It looks like it will be very LATE in the week, or maybe next week!

eBuild-A-Thon and BBQ

By Invitation
Eldon Brown - WA0UWH
is again Sponsoring a 

"eBuild-A-Thon and Bar-B-Que"

For Local Area
HAMs and
Hobby Electronic Builders
at 
The Mariah Ridge Ranch
11625 263rd AVE SE 
Monroe, WA 98272
(map)


The Third Saturday of each Month
10:00am - 5:00pm

Aug 15, 2009 - Done
Sep 19, 2009 - Done
Oct 17, 2009 - Done
Nov 21, 2009 - Done
Dec 19, 2009 - Done

2010 Events - Not Scheduled yet

No Admission Charge
Just Friends Having Fun


This is an Invitation-Only Event, 
But, if you have heard me talk about it,
you are invited.


Come Join the Fun; 
Bring a Project, Start a Project,
or Just Eat, Talk and Watch others
with their Projects.

This event is for
Beginners and Experts alike,
Ask, Learn, Teach, Show and Tell.


To help us plan for expected attendance - please sign up below.

Please RSVP Here
(admin)


Additional Presenters, Demonstrations and Facilitators are needed and Welcome ( describe on the sign up sheet ).


In case of inclement weather - lots of covered Bar-B-Que space is available

A Typical Project - A Direct Conversion Receiver

A Quick Project - A Crystal Oscillator

The eBuild-A-Thon

Demonstrations of printed circuit board; drawing and layout, printing, and etching will be provided.

Bring your; Ideas, Projects, PCB  Art work, Laptop or Files, Soldering Iron, Small Tools,  Parts, and Circuit Board Material.

Some parts and circuit board material will be made available on site for purchase.

Power and work bench space are available.


Demonstrated Building Techniques can be included upon request:

• Laser Print Etching
• The Manhattan Style
• The Ugly Style
• The Vector Board
• Surface Mount Techniques

For the beginner, Sample projects will be suggested.

Internet, WIFI, and Laser Printer Service will be available.

A PCB Etch will be available.

Shop and Sheet Metal Tools Available (usable with instruction or your expertise):

• Shears
• Notcher
• Punch
  
• Box and Pan Break

For the more ambitious, other larger tools are available (usable with instruction or proficiency and as time permits):

• Mill
• Lathe
• Drill Press
• Drill Mill
  
• Saws
• Wood Working Shop Tools
  
• Grinder
  
• Buffers
• TIG, MIG Welder and Plasma Cutter
  

Oh yes, the Bar-B-Que:

• A Bar-B-Que fire pit will be provided, bring your own Hamburger or Dogs, and Pop for drinks.
• Buns, Chips and Condiments will be provided.
• After lunch, Walks around the Ranch, up to the Ridge, and to WoodsCreek are suggested, maybe bring a fly rod?

Young builders, 12 year of age or older with building projects, are welcome with an accompany adult ( we love them, but DO NOT have facilities or activities for small children, please leave them at home to play ).

-

A new Marker Oscillator

This is my first completed HB DipTrace Designed PCB using Toner Transfer Method. The board is 1.25 x .75 inches with 16mil signal traces. Time to build this project, from Pressing "Print", to "Turn on" was about 1 hour.

This project is a 30m Marker Oscillator with Key Switch.

The oscillator uses all SMD parts, except; the Voltage Regulator (LM7805), Switch, Crystal, Trim Cap, and the Antenna (the Cap with a lead sticking straight up) which are full size components.

It worked the first time and was on frequency with just a twist of the Trim Cap, it seems to be very temperature stable and hand capacitance does not seem to effect frequency. I am very pleased!

Solder Paste applied and Ready for SMD Parts

SMD Parts on, Ready for Oven or Soldering Iron, In my case I used a small tip soldering iron. That is the 2N3904 SMD oscillator in the centre. The thing that looks like a TO-92 transistor (see below) is the LM7805M voltage regulator.

Completed and Aligned to Frequency on 30m at 10.140100mHz,
at top of QRSS Segment and bottom of WSPR Segment.

- Project Done -
Time to Build, About 1 hour

pQRP P&C Meeting

The following was reported by Wayne, after our Puget Sound QRP (pQRP) Pie and Coffee (P&C) Meeting, republished here as an archive.

Note: I did not invent the Toner Transfer Process to produce PCB's, I used a lot of information form the WEB, thanks to the many people that have gone before me.



Hello All,

We had a great turnout at P&C last evening, with fourteen of us around the table. Here's the list:

Roger, K7RXV
Jeff, KO7M
Rod, WE7X
Eldon, WA0UWH
Charlie, K7KN
Bob, W8MCJ
Rick, K7MW
Lyle, KK7P
Doug, W7RDP
Rich, AC7MA
Brendan, N0BML
Bill, WA7NCL
John, KC7NVE

Although most of us have been busy with summertime activities, there have been a few projects going on.

Eldon, WA0UWH, has worked out a method for producing PC boards, using an ink transfer method involving a laminating machine. He'll have to explain it in detail for us, but it looks very interesting.

He brought his 40 dB Tap project along for show and tell, also, having cut the PCB material to Roger's specifications and now getting ready to build it.

Eldon is making his shop available to any of us on the 3rd Saturday of each month, for radio or other types of building projects. He has everything from wood working equipment through metal working gear, including a lathe and milling machine.

Lyle has built his RF Test Set, and his lack of output from the DDS board was caused by the fact that his DDS60 is an older one with a different DDS chip and clock frequency. Rich is going to try to adjust the firmware so that Lyle will be able to use the older daughterboard.

I have been so busy with being the Commodore of my local yacht club, hosting company, and the usual summertime activities, that I have not been doing any building projects and have not been on the air, either. My time will free up a lot in late October, and the onset of the rainy and dark season will turn my interests back to the workbench and paddles.

Jeff, KO7M, brought his recently built HF Packer Amp, that he built from a kit, and it is very nicely packaged and will be a nice addition which will give his QRP RF output a good boost to help make contacts in this time of low sunspot activity.

Bob, W8MCJ, came with a box of free stuff like coax cables, some ham related books, and gave a copper ground strip with braided connecting wires to tie rigs together and to ground as a door prize. Lyle gratefully received this unit.

As usual, the discussion around the table was varied and lively, ranging from a little teasing towards Doug, W7RDP, about the recent docking mishap with the Wenatchee, the Washington State Ferry he works on, to various computer programs for MAC and Windows Vista, as well as QRP Radios and operating events.

Bill, WA7NCL, talked a bit about operating in a recent "Bumblebee" event, and made a suggestion for next Salmoncon, saying that since we tend to focus on building projects, we should have an operating event at Bowman Bay, where we each put together a portable QRP station, hike over to the point, throw an antenna over a tree, and operate for a while. Could be a lot of fun.

Rod, WE7X, brought in an award that he and Doug, W7RDP, had won in a recent VHF Contest. Roger, K7RXV, had been along on that trip as well, but didn't operate.

Brendan, N0BML, talked about his building project at Eldon's last shop gathering, which was a homebrew charger unit for his cell phone. Brendan is also practicing CW and getting ready for an upgrade to his license.

If I missed anything, it was simply because there was so much being discussed.

In short, it was another very enjoyable evening.

73,

Wayne NB6M

Building more PCB's

I have been working on several PCB projects. This is one that has taken some time to perfect. These are 16mil traces, 12mil clearance for 1206 parts. The ground plane grid is 15mil on 30mil centers. DipTrace was use for layout. PCB production time from "pressing  print" to "finished PCB" was 18 minutes.

This is a SMD Crystal Oscillator Marker. I will use it for a 30m QRSS Band Edge Marker. My past "Ugly Style" construction version of the same circuit has been very stable, even without an oven or shielding.

For this board, my only reservation is;  I wished I had incorporated a push button on/off switch - I may have to redo this board.

It is almost time to load the parts, . . . or start again.  One nice thing about a cheap and easy process - "do overs" are easy. Maybe, too easy, I did not spend enough time thinking about the intended function(s).