Swan 350

Swan 350 circa 1966

This is a radio I have never used before.  The Swan 350 was a popular rig in the 60's and 70's.  I repaired this one for my friend John W3JOI and enjoyed using this rig.  The radio is an interesting design using a single crystal filter in the IF.  The radio is powerful and has a good sensitive RX.  I also got to use a D-104 mic for the first time.  This radio will pin my 200 Watt meter quite hard and gets good audio reports.  It only took a couple of tubes to get it going again.

I checked into the Swan Tech Net today and was told the S/N of this radio (C 618852) was manufactured in 1966 and that the radio was produced from 1964 to 1967.  This one was late enough to have the one piece xtal filter instead of sockets for the individual crystals that the early ones had.  During testing I measured the B+ ripple at about 3v.  Stu K4BOV said that the it should probably be less than 1v so the filters are a bit weak.  Stu suggested to use 80-220 mfd caps rated at, at least 350.

The Swan Tech Net is on Sat PM at 2:30-3:30 or so on 7235.  Check it out sometime if you are interested in these oldies.

Fictional Character eligeble for Elser-Mathes Cup for Mars QSO!

Just finished reading this book.  It has some radio in it and even a Character that would be eligible for the Elser-Mathes Cup  http://www.eham.net/articles/222 for the 1st contact with Mars.  Not quite ham radio but a pretty good story.  If you are a science nerd you will enjoy the story.  I am a bit surprised that it is not a Young-Adult book.  Some good suspense and science.

For more about about Fred Elser seehttp://www.para.org.ph/membersarticles/PI-3AA/KA3AA.htm

New to me TR-4C

New to me TR-4c

New TR-4C is on the air.  This was an eBay purchase that checked out and seems to work fine.  Several of the tubes did not light at first but they all checked good on the B&K 707 tube tester.  The previous owner had swapped out the 3/16" mic jack for a 1/4 one with 'non-std' mic and ptt wiring so I changed it to match the Tip=PTT and Ring=Mic that Drake uses on the stock 3/16" connector.  I found an old Turner 454 SSB that had a 1/4 plug on it and it seems to work.  The pig tail on the AC-4 is not picking up the Spkr Audio but the headphone jack sounds great.  Will rag it off some and maybe put a drop of oil on the PTO bearings and I think it will be pretty good.

ARRL International DX CW

 Band    QSOs    Pts  Cty
   3.5      23      69   18
     7     132     396   59
    14     165     495   77
    21     148     444   73
    28      57     171   30
 Total     525    1575  257
Score: 404,775

This included a couple of new countries.  One was Antarctica on 20M,  DP1POL who confirmed it on LOTW.

Set-up for the contest:
FT-1000mp Mk V
Alpha 78
Cushcraft R-7 (end fed half-wave vertical)
N1MM logging software
Digimaster 780 for 'help' with copying
Koss Headphones
Vibroplex Code Warrior Jr.

Before getting on the contest both the QSK amps were 'down' and This crimp on the filament wire in the P1/J1 connector had failed.  The 'hot' spot has been there for the last few years but cleaning it and tighting the pin up 2 years ago seemed to 'fix' it.  This time the crimp NOT the conection at the pin itself gave up.  I cut the pin off.  Cut off a bit of the red wire and installed a short 'by-pass' jumper of 1" of #16 wire which fit the crimp better.  The red wire was maybe #12 or #10 and was really too large to be properly crimped.  I carefully opened up the crimp and re-attached the new smaller wire then made a loop and soldered ti to the original large wire.  Some tape and it seems to be holding.  For now anyway.

Classic Universal Sound Card Interface

This interface by Skip Teller was put to use this past weekend with the FT-817 and a laptop running N1MM and using an end fed half wave wire down the 2nd floor hallway during recent trip to Lovettsville, VA.

The interface is described in the Jul 2010 QST
The Classic Universal Interface has two isolation transformers and an opto isolator to run the PTT line from the computer serial port.  I used a Radio Shack Gigaware USB to Serial Converter and this works well once you figure out the port the converter is using.  It helps to look at the Device Manager on the computer.  Then you have to tell the program you are using to use the correct pin on the serial port.  An earlier and later ver of KH6TY Skip Teller interface using an audio derived VOX signal to trigger the PTT line which will also work.

All of the interface boards seem to be sold out on Skip Teller's site but FAR Circuits lists the VOX board from the June '09 QST Sound Card Interface for FM Transceivers.
http://www.farcircuits.net/modem1.htm

New DigiVox Interface Mar '11

There is also a newer ver of the VOX interface from Mar 2011 QST article.

Happy New Year 2012

J38 on Straight Key Night

Happy New Year
When I was a boy starting out in radio I bought one of these keys from a TV repair shop in Madison NJ for One dollar.  It was brand new in a Lionel box and I used it for many years.  Eventully I sold it at a hamfest but bought another years later to use for ARRL's straight key night.  I try to get on and make a contact or three on New Years Eve or New Years Day.  This year only made one contact with KA2PJO 'Tony' in NY on 40M CW.

FT-1000MP Mk V CAT Port Failure

MAX232 chip in MP

I found out that the 'CAT' port chip a MAX232CWE  is not very robust.  When testing the End Fed antenna at hi power the computer connection dropped out and this chip is a common failure.  The CAT cord has home made and not well shielded for one thing.  The chip is pretty direct to the cable on the computer side and they tend to fail in hi RF situations in other types of gear as well.  The good thing is that they are inexpensive and I ordered two from DigiKey for about $3.70 each.  Some experience with replacing SMD parts is suggested.  You will need a jewelers hood and a bright light as well as a small pair of flush cutters, and a small enough iron to complete the job.  The chip is accessible with removal of the covers only.  No other dis-assembly is required.  Unfortunately I did manage to pull some traces off the board due to not being gentle enough in removal.  I was able to repair on trace with a single strand of copper from a CAT V wire and I wired two pieces of enamel wire direct to the connector pins.  Not pretty but it works.  I did not follow the advice of another repairer who suggested using a cutter to remove the chip.  I cut one side off but I heated the other side with the desolder gun. Usually I have had good luck removing SMD parts this way but NOT this time! Using a cutter and then removing the pieces carefully is the way to go.  The desoldering gun or braid can be used to assist removal of the pieces of leads that are still on the board. When the board is clean and smooth place the chip over the pads and solder it back on using the smallest iron you can get.  Pins 8 and 9 pads lifted off the board too but there is no connection to these two pins so that is 'OK'  Use the schematic and make sure that all the connections to the new chip are good. Here are some notes I used at the bench for my ohmmeter checks.

Pin 1  and Pin 3 C5011
Pin 2 and  Pin 16 C5012
Pin 4 and Pin 5 C5018
Pin 6 C5018
Pin 7 RS162
Pin 8 N/C
Pin 9 N/C
Pin 10 Busy Pin 15 on Q5035
Pin 11 C90 CAT TX 8pinchip
Pin 12 C81 CAT RX 3pin
Pin  13 TX pin 3 RS-232 connector
Pin 14 RX pin 2  "             "
Pin 15 GND
Pin 16 C5012

Check all these with ohmmeter to make sure the chip is soldered in correctly and that all the traces are good and it should work.  I used no real static protection.
In addition to replacing the chip I also purchased a fully shielded RS-232 Cable with RFI hoods on the connectors and put some 'Beads' on each end of the cable.  Not sure this will help but changing the chip is not  going to be any easier the next time.

Thanks to Hal for these directions
Dear Paul, Unfortunately for me, I did the same thing on my MarkV,and had to
change the chip. There are web sites that have good explanations on howto
perform the surgery. The chip is a huge SMD with what looks like a billionwires.
The idea is to buy more than one replacement so you feelcomfortable if you screw
up. The good procedure is to clear a table top, put down layers ofterry cloth
towels, get some good high-intensity halogenlighting up above your head and
aimed from two differentdirections, plus a smaller halogen goose neck to getreal
close to the board. The next good idea is to fabricate a chassis ground gromthe
radio frame to the a.c. electrical ground. Then, obtain a static wrist strap and
secure it to thegrounded radio frame. Now you are ready to yank off the covers
to the radio. Start with all the top stuff, flip the radio over andremove t
bottom covers. Have the rear apron close to you and look down intothe radio near
the left edge as appearing upside down. The '232 chip is close to the rear
apron. Tie off as much of the cabling as you can to exposethe chip. Make sure
you identify what direction the chipnumber one lead faces! Use a flush-cut
dikes, ( a good pair, not junk) and cutall the wires off the '232 chip. The pull
the chip body away. Using a needle-point soldering iron like a Weller W60P andan
electronic tweezers, heat and pull up the remainderwires from all the pads. When
done, clean pads with 10 % MEK / 90% Alcohol mixture,and a toothbrush / rag. Use
a magnifying glass to absolutelyconfirm all the debris is gone. This clean up
process may takehours. Go slowly, don't overheat the board. The chip lands need
to bebright and shiny when you're done and the tiny spaces between the landsneed
to be clear of debris. A #11 scalpel lightly applied with blade upis a good way
to shovel this debris, followed by the toothbrush and rag. Tin the iron well.
Tin the lands, one by one with a tiny addition ofsolder to each one. Get yer new
chip, face it correctly and use 1 tiny drop of Barge cementunder it and lay it
down so all the lands and wires line up exactly. Holduntil you feel the chip is
settling into the cement. Wait 1 day. Recover your nerves. Back to it: Tin the
iron's tip well, and do this every lead. Heat every lead so it melts the solder
under it. Be quick about it, which is why the iron is important to beclean.
Inspect carefully. Use the toothbrush, scalpel, magnifier. Removedebris. Yer
done. Button up and continue hamming. HalW4HBM