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My favorite way to store diodes, transistors, ICs, is to use a 4x6" pink zip-lock anti-static bag for each type. they fit perfectly in standard 4" cardboard stock bins, so you can fit many types per bin, and easily add or remove parts in sequence. this allows inventory to expand easily while keeping parts in sequence. mark the part number clearly with a permanent sharpie on the top portion of the bag, and you can quickly zip through them to find the part you want.

this is how I store all my tek and hp parts (including small pots, lamps, etc.), and thousands of 1N/2N numbers. where needed, I use a smaller gray anti-static bag inside the pink bag for very sensitive mosfets parts, or use anti-static foam to seat the parts inside the bag..

this has worked for me for 30+ years, and you can get the pink anti-static bags off ebay cheaply. I buy the cardboard stock bins for a local shipping box company. never had a damaged part in all these years.

I DO NOT recommend plastic acro bins or drawer cabinets. they are fine for hardware, just not for semiconductors. they are also a nightmare to expand as parts are added.

all the best,
walter

--
Walter Shawlee 2
Sphere Research Corp. 3394 Sunnyside Rd.
West Kelowna, BC, V1Z 2V4 CANADA
Phone: +1 (250-769-1834 -:-
We're all in one boat, no matter how it looks to you. (WS2)
All you need is love. (John Lennon)
But, that doesn't mean other things don't come in handy. (WS2)

On 12/3/2018 2:59 PM, Fabio Trevisan wrote:

Hello Guys,
I come to ask your ideas (or how do you guys do) on the best way to separate and store assorted transistors.
With the years, I came to scrap and possess quite a number of transistors of all kinds (maybe a few hundreds).
I know that this amount is still few in comparison to what probably some of you guys have, but they're enough to annoy me quite much whenever I need to browse them, looking for a possible candidate for a new project or to use as a replacement of something that may have blown.
The thing is, I can't afford the space to have separate drawers for each possible model, so I would like to separate them in some sort of matrix, that is easier to browse later on.
Then, when I get to a given bin, I may need to look for the best part number only in that bin.
But I can't seem to find a good way to sort them...
I thought about four drawers, each with maybe a dozen or sixteen bins (4 x 3 or 4 x 4).
The four drawers would be Small and Medium PNP (or P-channel) - Small and Medium NPN (or N-channel), Large PNP - Large NPN.
Up 'til here, I think it's just common sense to have these 4 major separations and I can`t think of a better way to go about it.
Now, within each drawer, I can't seem to make up my mind about the best way to sort them...
By Vce (Vds) across one axis and by Ic (Ids) across the other?
Which 2 major selection parameters are the most useful?

I welcome your suggestion / wisdom...

Rgrds,

Fabio

I've had great luck using snap lid pill boxes like those SMTWTFS type found in the pharmacy department of just about any big box store.
I just put a type label over the day stamp

-- Bert.

I use #1 coin envelopes folded in half. A small stack held together with a rubber band fit into a compartment in the Plano trays that I store them in. The trays and their compartments are numbered, and recorded in my transistors spreadsheet so I know what I have and where to find a part.

Dale H. Cook, Radio Contract Engineer, Roanoke/Lynchburg, VA

Hi Fabio, My view, by type and then note-book cross reference Vce Ic or whatever other characteristic..

--
Jack

any trouble with electrostatics using those bag? Tom
--
Jack

On Mon, 3 Dec 2018 17:04:15 -0500, you wrote:

If you have more than a couple of each, get small pill bottles with
snap on caps, write the device number on top and keep them in order.
Make small trays slightly higher than the bottle and you can stack
them in a drawer. You could probably stuff a couple hundred in a
drawer.

Not my idea, I saw a collection of smd parts organized that way
(using smaller vials) and it was pretty impressive.

I use bead organization containers for SMD parts. Locally, Michaels
or Hobby lobby may have them. You get about 20 screw top plastic
vials in a plastic case for not too much (look for sales). These are
about 1 inch in diameter.

I put a 3/4 inch colored dot label to discriminate between 1% and 5%
resistors, for instance.

Some containers are available in a 1 3/4 (or so) diameter. Those can
be used for tape mounted SMD parts.

Be aware that these containers are not necessarily anti-static.

Things that need static protection may be left in the tape which can
be cut or curled to fit the container.

Other containers for beads, especially with locking tops, are good for
screws and nuts.

Harvey

Paul

I would think if it is a dead NVRAM, holding in the B-TRIG button as you
power it up will cause a reset. See if that gets it booting.

Dave

On Mon, Dec 3, 2018 at 3:34 PM benj3867 via Groups.Io <benj3867=
[email protected]> wrote:

Hi guys,

I have a TDS 3032 that does not start. When powered on, the fan spins, and
the LCD shows a white screen (i.e., back-light only). There is no beep, no
floppy seek sound, and no relay clicks - the scope simply stays this way
and does not attempt to boot. All power supply voltages are within spec.
Pressing the calibration button in the back during power on has no effect.

Any ideas as to what may be the cause of this would be most welcome!

Can it be a dead battery in the Dallas NVRAM chip? I know this can cause
weird problems at startup, but I do not know if this is one of them.

Thanks in advance,
Benjamin

If you have more than a couple of each, get small pill bottles with
snap on caps, write the device number on top and keep them in order.
Make small trays slightly higher than the bottle and you can stack
them in a drawer. You could probably stuff a couple hundred in a
drawer.

Not my idea, I saw a collection of smd parts organized that way
(using smaller vials) and it was pretty impressive.

Paul

--
Paul Amaranth, GCIH | Manchester MI, USA
Aurora Group, Inc. | Security, Systems & Software
paul@... | Unix & Windows

On Sun, Nov 18, 2018 at 7:42 PM EJP <esmond.pitt@...> wrote:

I also have several of Ed Oscarson's from last year and they work really
well. Siggi's model probably preferred on the grounds of no melting
required, provided the catches work.

I got an email from someone who tried the Shapeways prints. Apparently they
work just fine, though he had to use pliers to get the clip to latch.

Here are the links, in case anyone else needs some:




I don't take a markup on those, and the models are free to use as you like:
.

Siggi

I use 'Coin envelopes' available at most office supply stores. Write the
part number on the envelope and store in numerical order in a cardboard box
partitioned to fit the envelope width.
You can fit a LOT of parts in a small space.

HTH Tad

Small plastic bags with a ziploc, widely available on fleabay. Many can then be put in a single component drawer. Choose bag size so it fits into drawer without folding. Put a paper label inside the bag, if that helps locating devices in the future.

Care with static-sensitive devices, of course.

You and the rest of us!
Jim F


Sent from my Verizon, Samsung Galaxy smartphone

Sigh,
It's a good thing I don't live near there if I want to keep my marriage working. Just a few weeks ago I picked yet another scope (two dozen and counting). A fully loaded 7704A with two extra plug-ins and a non Tek probe. I didn't need it but at $130, what does need matter?
Bob

Hi guys,

I have a TDS 3032 that does not start. When powered on, the fan spins, and the LCD shows a white screen (i.e., back-light only). There is no beep, no floppy seek sound, and no relay clicks - the scope simply stays this way and does not attempt to boot. All power supply voltages are within spec. Pressing the calibration button in the back during power on has no effect.

Any ideas as to what may be the cause of this would be most welcome!

Can it be a dead battery in the Dallas NVRAM chip? I know this can cause weird problems at startup, but I do not know if this is one of them.

Thanks in advance,
Benjamin

Hello Guys,
I come to ask your ideas (or how do you guys do) on the best way to separate and store assorted transistors.
With the years, I came to scrap and possess quite a number of transistors of all kinds (maybe a few hundreds).
I know that this amount is still few in comparison to what probably some of you guys have, but they're enough to annoy me quite much whenever I need to browse them, looking for a possible candidate for a new project or to use as a replacement of something that may have blown.
The thing is, I can't afford the space to have separate drawers for each possible model, so I would like to separate them in some sort of matrix, that is easier to browse later on.
Then, when I get to a given bin, I may need to look for the best part number only in that bin.
But I can't seem to find a good way to sort them...
I thought about four drawers, each with maybe a dozen or sixteen bins (4 x 3 or 4 x 4).
The four drawers would be Small and Medium PNP (or P-channel) - Small and Medium NPN (or N-channel), Large PNP - Large NPN.
Up 'til here, I think it's just common sense to have these 4 major separations and I can`t think of a better way to go about it.
Now, within each drawer, I can't seem to make up my mind about the best way to sort them...
By Vce (Vds) across one axis and by Ic (Ids) across the other?
Which 2 major selection parameters are the most useful?

I welcome your suggestion / wisdom...

Rgrds,

Fabio

Hi,
Indium is also used by the Vandervell Co. for their tri metal copper lead engine bearings as the overlay to the copper for the actual bearing surface. The US uses lead as the overlay but the English/Vandervell process used lead/indium and hold the patent for it. The lead/indium is a better bearing surface.

Jim O

Hi Chris,

It's not so easy to interpret the graphs 26 and 27 the correct way. The shaded area in 26 actually consists of horizontal lines, the value of which are sampled when the memory gate conducts. In 27 something similar for the rest period between end of hold-off and next trigger event.
When probe TP555 at a slow sweep speed, 5 ms/div, trigger from this signal and play with the SCAN rate of the 7T11, you can get a more or less stable display. You will recognize the 7T11 sweep as a rising envelope with an amplitude of 5 V. The output at TP564 is a nice 2X inverted, down going sweep signal with amplitude 10 V. TP556 shows about the same as TP564 but with small amplitude.

Albert

As noted by other posts, it may be indium. If so, it’s melting point is 313F (easily reached in an oven). It has a very low vapor pressure (also noted) so it is suitable to high vac systems. Typically used for soft metal seals and thermal transfer joints. It’s Young’s modulus is 11GPa (similar to wood!) so it deforms easily, fills voids and contours even at low temperatures. It will wet many metals, so maybe it is there as a thermal conductive layer.
If it is indium, it will talk to you (squeak) if bent by the ear. Something to do with crystal migration.
Kjo

On Sat, Dec 1, 2018 at 10:49 AM, Albert Otten wrote:

The memory gate is open when Q546 conducts, so when its base is pulled
negative. For this to happen, *both* gates B and D outputs have to be low. In
rest D is low but B is high. Then when B also goes low the base of Q goes
negative and the memory gate conducts. Some 2-3 us later D goes high, base Q
goes positive and the memory gate closes. Again some us later (end of
hold-off) both B and D switch to the opposite states.

I've now had another look at this and found at least one fault with my plugin. I see the multivibrator behaving as you describe, and outputs B and D do indeed spend a couple of microseconds low together. The reason that Q546 was never turning on was that R542 and R541 have drifted in value. R542 should be 30k but measures 26.2, and R541 should be 27k but measures 28.5. That meant that Q542 was stuck on and thus clamping the base drive to Q546. I've desoldered R541 and R542 for now.

Now I have healthy gate pulses at the collector of Q546. However, I don't have any sweep at TP555 in equivalent time mode. Need to look in to this next.

Chris

I have no affiliation with the seller, but he has a lot of equipment (Tek) for sale via Craigslist,
located
about midway between Washington DC and Baltimore MD (USA):

Wow - what a haul. The big mainframe on the cart is a 7904A, and has a 7CT1N curve tracer in the
second bay. That in itself is a nice and exceptionally useful thing.

Craig