[NLRS] 10 GHz kits

[Bud Patten]

Great advice Doug,
I like the flux pen from Digi-Key (Flux Pen - Formula 951 No Clean -
KE1804-ND) and then use alcohol to clean up afterwards.  It also helps to
lay off the coffee for a couple of days before starting a  project like
this..... ;-)

Bud
w0lcp

Please check out my Web Site:  www.qsl.net\w0lcp
and the Northern Lights Radio Society website at:
http://nlrs.dropboxone.net/index.htm
----- Original Message -----
From: "Doug Reed" <n0nas@amsat.org>
To: <nlrs@mailman.qth.net>
Sent: Friday, January 03, 2003 9:15 AM
Subject: Re: [NLRS] 10 GHz kits


> At 09:43 PM 1/2/2003 +0000, kb0mnk@visi.com wrote:
> >If it makes a differnce for anyone thinking about a kit and getting on
> 10GHz I
> >would be willing to help tune it up. I have a power meter, attenuators,
> 12.4GHz
> >freq. counter, Rubidium clock, an older spectrum analyzer and several
> >synthesizers. It makes tuning pretty easy.
> >>Quoting "mike@KB0OZN.com" <mike@KB0OZN.com>:
> >> Hi Jon and all, I'd like to echo the interest in a kit, but am
concerned
> >> about the complexity of tuning etc.  Any information would be great.
> >> Thanks
> >> Mike
> >> KB0OZN
>
> I'll join in with a little hear-say too. I spoke with Marc at the Aurora
> meeting when he was showing the kit. I was intrigued that it was so small.
> Since I'm working with surface mount every day, the "large" 1206 size
parts
> didn't scare me but I was worried about tuning. He said the kit was
> designed with metering points for each tuning stage similar to the way it
> is done in Motorola or GE two-way radio gear. The whole tune-up can be
> accomplished with a volt meter. Of course you'll probably need a signal
> generator to verify receive operation, a frequency counter to put the LO
on
> frequency, and the power meter to verify you have output.
>
> I think the only negative comment he had was regarding soldering the
> tin-plate box around the board and either not getting the right height or
> ending up with pre-drilled holes for feed-thrus in the wrong place.
> Something similar to that anyway.....
>
> I've been intending to order the kit this winter. If there is a way to
> shave another $100 off the price, I'm even more interested.
>
> And I'll throw my hat in the ring to help getting them going if needed.
I'm
> pretty sure the 18 GHz spec-an at work can help with tuneup of the LO and
> transmitter chain. But we don't have a 10 GHz signal generator for
receiver
> tests.
>
> The single most helpful piece of equipment for surface mount work is still
> a microscope. That plus a very small point on the soldering iron and very
> small diameter solder. I find 7x power to be just about perfect, more than
> 10x is too much. The microscope and a strong light make checking your
> solder joints pretty easy. Since you probably don't have a scope, just use
> anything that will get you some magnification and a strong light to work
> under. A 10W or 20W halogen lamp at 6" or a 60W incandescent lamp at 2',
> not the overhead ceiling lamp.....
>
> The easiest technique is still to have a little bit of liquid or paste
flux
> on the board, place the part in the flux with tweezers, then hold it
GENTLY
> with a toothpick (or non-magnetic tweezers) while touching the solder iron
> tip (with solder) to one end of the part. When you get all the soldering
> done, use rubbing alcohol and a soft "acid brush" to clean all the flux
off
> the board. The less flux residue left on the board, the fewer problems
> you'll have with sensitive parts like mixer ICs..... The flux we use at
> work is a "no clean" flux that is very inactive, but I still clean it off.
> And you don't need much flux. Using a Q-tip to mop the flux on the pads
and
> remove all but a thin film is about right.
>
> Another option for soldering is to put a small layer of solder on ONE pad
> of the part. Then add flux, lay the part in place, hold it GENTLY while
> applying heat to the solder on the pad. The part will sink into the solder
> and be soldered and stuck in place when you remove heat. Solder the other
> end, then come back and finish soldering the first end. As long as you're
> using flux, the joints should come out OK.
>
> The only other thing I can think of to caution about is the soldering iron
> itself. A 600 degree tip should be perfect for soldering small surface
> mount parts. A hotter iron begins to raise the possibility of damaging the
> PCB traces if your soldering technique isn't good enough. I always got by
> pretty well with a pointy tip or a flat chisel tip. The common chisel tip
> is about 1/8" wide and I usually found myself using just one corner of the
> tip. I don't remember looking closely at the DB6NT board but I assume the
> parts are not super close so having a tip that is slightly too large may
> not be the end of the world.
>
> If at all possible, try to have a grounded tip soldering iron for doing
any
> semi-conductors. If the iron isn't grounded, the first touch could blow
out
> a transistor or mixer chip. They have even replaced the older Weller
"click
> thermostat" irons at work because they might generate a magnetic field and
> blow out some of the more sensitive chips we use. I don't think that
should
> be a problem for this project and the old Weller soldering station is all
> I've used for surface mount the previous 8 years. Worst case, you can heat
> your old ungrounded solder iron up, unplug the cord and ground it before
> soldering the ICs. Then plug it in and heat it up again..... But with luck
> and good anti-static technique, it shouldn't be a problem.... Good luck!
>
> How about that.... Two paragraphs on the kit and 5 paragraphs on
> microscopes and soldering irons..... Just a bit off topic....<g>
>
> 73, Doug Reed, N0NAS.
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