EMRFD Message Archive 1059
Message Date From Subject 1059 2007-09-27 08:28:08 jac.clement Favorite Parts list
that I am always using, so I don't have to dig them out of the huge
database each time I need them?1060 2007-09-27 08:44:18 Roger Hayward Re: Favorite Parts list
I was a little confused at this question when it posted. I think what
you are asking is if there would be a good list of components to have
on hand, perhaps a sub-set of everything that digikey offers :) .
(The digikey catalogs are getting so thick they don't fit through the
mail slot any more).
This is a tricky question to answer. For starters, most experimenter
hams I know tend to be pack-rats. We pick up components as we see
them, or feel there is a need, and most-likely wind up with a basement
full of stuff to leave for our kids to sift out after we're long gone.
(Thus the motivation to talk our kids in to getting a ham ticket, hi).
If you are interested in experimenting with HF circuits similar to the
examples in EMRFD, I'd suggest you start with an ample supply of
2n3904 and 2n3906 transistors. Find either a starter set of 5% 1/4W
resistors, or choose from some of the more common values. Buy these
in bags of 100 or 200 at a time (they are very cheap). From there,
0.1, 0.01 and 0.22uF capacitors (and 10uf electrolytic) will get you
started. For Toroids, Amidon FT-37-43's and a few -6 and -2 cores are
staples in the journals.
W7ZOI mentions quite commonly the notion of having a junkbox in your
basement. Well I've seen his junk box, and it is deep AND wide (and
pretty organized actually). You can do quite a bit with a smaller
sub-set of "popcorn" devices, such as the 2n3904's.
Here's where the fun begins though. When you see a schematic that has
a 3.9K resistor somewhere, don't sift through the house (or run down
the street) to find a 3.9K. If the closest thing you have is a 4.7K
resistor, study the circuit to determine what will happen if this
value is changed a little bit. If you are setting the DC bias on the
base of a transistor, aim for the right voltage at the base, and use
the components you have on hand. Sketch the values you chose in your
notebook (or right in to the book for that matter) and move on. When
you can test a stage at a time, you can see the effects of your
choices immediately, etc. The same goes for the selection of toroid
windings. Sometimes I have to take the authors description: "12
turns on a T50-2," and calculate what inductance that is. From the
inductance, I can work backwards to figure out what I have to do with
my T25-2. (This example doesn't work, because I probably couldn't get
12 turns on a T25-2.....I know someone who could though, and probably
do it in something like 7.4 seconds).
The other place to look is hamfests, eBay, craig's list, or "Dan's
Parts" on the web (google it). Dan always has air variable
capacitors. You can never have enough of the smaller 390pF air variables.
In order to compile a good sub-set list, sift through a few chapters
of EMRFD and just study the schematics. You'll tend to see some of
the same bipolar transistors, J310's for generic FET's, etc. You'll
actually be able to tell which 5% 1/4W resistors must be in ample
supply in the author's shack as well.
For some of the phasing receivers, some components have extremely
tight tolerance on them. For these, we really do need to purchase 1%
values. This is an excepti1061 2007-09-27 10:07:31 Sam Morgan Re: Favorite Parts list
> I was a little confused at this question when it posted. I think whatsnip
> you are asking is if there would be a good list of components to have
> on hand,
>
I know this doesn't address your question as to specific values, but I finally
just decided to grab a bag of values to fill out my junkbox I have been trying
to build up from components striped out of computer motherboards, power supplys,
and anything else electronic that I have been able to find broken and abandoned.
(proud member of 'Dumpster Divers-R-us')
one item I had been unable to salvage enough of, is capacitors,
I have been searching online and found this bag of caps:
http://www.allelectronics.com/cgi-bin/item/CK-1/140/224_PC_CERAMIC_CAP_SET_14_VALUES_10PF-220nF_.html
I wonder if others have found another grab bag styled package they could post
the link to before I buy this one?
Surprisingly I found Rat Shack has a 500 count 1/4 watt resistor pack that was
cheaper to buy locally than it was for me to deal with shipping from some other
source.
http://www.radioshack.com/product/index.jsp?productId=2062306&cp=&sr=1&origkw=resistors&kw=resistors&parentPage=search
Same for slide switches for building an attenuator, RS was my best source.
I guess if I could build up a large $ order I might would/could buy from other
sources, but monies come more in the $5.00 and $10.00 sizes for me;-)
Anyone recommend any other sources for transistors and diodes out there
competing with Dan's Small Parts?
--
GB & 73's
KA5OAI
Sam Morgan1062 2007-09-27 13:27:57 Greg Derda Re: Favorite Parts list
> Anyone recommend any other sources for transistors and diodes out
> there
> competing with Dan's Small Parts?
mode." Besides Dan's, here a couple more sites with good deals on
parts needed for the circuits in EMRFD, SSD, & W1FB's books....
http://www.angelfire.com/electronic2/index1/ (metal jFET's, mosfets,
mk484's, etc.)
http://www.kitsandparts.com/index.asp (great toroid and cap kits,
mixers, tuning diodes)
There are a couple of sellers on Ebay that carry this same type of
stuff - search for specific terms like "mosfet," and "455 khz" to find
them, then look at the other items they have for sale.
73'
Greg
ki4mmm1063 2007-09-27 14:11:35 michael taylor Re: Favorite Parts list
> >I often get my transistors and diodes from mainstream dealers like
> > Anyone recommend any other sources for transistors and diodes out
> > there competing with Dan's Small Parts?
Digikey, Mouser, Jameco, also Newark has some odd ball transistors
that can be harder to find. One place that I infrequently use is
Future Electronics' Component Super Store,
<http://www.componentsuperstore.com/> they carry some RF transistors
and other parts (e.g. SA612) that are either expensive or not in stock
at DIgikey and Mouser.
For parts that are still in-production, I found Digikey and Mouser
competitive price-wise to Dan's.
For resistors, I bought a 2000 carbon film resistor kit from NorCal
QRP Club a few years ago, but those are sold out, and I replaced /
replenished it with a similar collection from a Asian eBay seller, who
was selling 1/4 or 1/8 watt 1% metal film resistors collections for a
decent price. <http://www.amqrp.org/kits/resistor/>
For capacitors, I bought a value pack or whatever from Jameco and
Maplin (UK) for common ceramic and electrolytic caps. Since then I
tend to overbuy specific values that I use often, for a better cost
per item, and slowly building up a stock of values I use often.
I have bought ferrite and iron powder torrids and ferrite rods, beads
from W8DIZ, "The Toroid King" at <http://www.kitsandparts.com/>, Doug
Hendricks <http://www.qrpkits.com/toroidkit.html>, Amidon Associates
<http://www.amidoncorp.com/pricing/>, and CWS ByteMark
<http://www.cwsbytemark.com/>.
-Michael, VE3TIX1066 2007-09-27 22:08:56 jr_dakota Re: Favorite Parts list
trimmer and tuning ... from Dan's ... his Special Deals and grab bags
can be a real source of 'treasure' if you don't mind sorting through a
lot of stuff (I got 5 500+ piece grab bags for 10 bucks on special
once, took a month to sort everything out ... and a week to pay for
itself)
As someone mentioned Parts and Kits is a good source for toroids, some
varactor diodes too as cheap as you'll ever find them .... he also
released a line very reasonably priced mini kits called RF Toolkits
that look like a lot of fun for those just getting started and want
proven designs and PCBs ... eventually he'll have enough blocks to
piece together complete systems (He's almost there now)
For general surplus deals here are a few other places I use
http://www.allelectronics.com/
http://www.alltronics.com/
http://www.goldmine-elec.com/default.htm
http://www.futurlec.com/index.shtml
http://www.debcoelectronics.com/
And I use Digikey and Mouser for the stuff I can't get elsewhere
And if all else fails I hit this list of links
http://www.epanorama.net/links/companies.html#dealer
JR
>from other
> I guess if I could build up a large $ order I might would/could buy
> sources, but monies come more in the $5.00 and $10.00 sizes for me;-)
>
> Anyone recommend any other sources for transistors and diodes out there
> competing with Dan's Small Parts?
> --
> GB & 73's
> KA5OAI
> Sam Morgan
>1068 2007-09-28 07:26:02 John Clement Re: Favorite Parts list 1089 2007-10-15 06:37:05 Allison Parent Re: Favorite Parts list 1090 2007-10-15 06:45:30 Leon Re: Favorite Parts list
From: "Allis