What did the NTE199 sub for?

"Dave" schreef in bericht news:aaedndfATcBFg2XTnZ2dnUVZ snipped-for-privacy@posted.internetamerica...

Well, if you asked it here, you can find it in the Google archives. FAIK the replacements mentioned were not very accurate. The NTE199s are known for low noise, high gain and low VCEsat. They are also widely available.

petrus bitbyter

Hey, thanks for the reply. Yes, the part is easily obtained, I'm just trying to find a model for it in Spice so I can work the bugs out of a project before I actually build it.

If I recall correctly, the sub was a 2SC part number, which NTE did cross over to their 199, I just can't remember what it was. And there is one version of Spice which was advertised as coming with a model for that particular part number.

All of this is available, I just have to find it. Thus, my original question... Anyway, if anyone reading this cares to lend a hand and look up the cross in their old refs, like they did before, it would be greatly appreciated. In the meantime I am looking through my old notes. I did find that it crosses to an SK3245,but that is not the part number that I found the Spice model available for. As I mentioned, I believe it was a 2SC part number. I have it written down somewhere, but finding that particular note might take a while. So I am coming here with my hat in my hand again. :)

Thanks...

Dave (Who is now searching Google.)

It replaced hundreds of other transistors. The NTE line is general purpose replacement parts, not really intended for new designs. The latest printed NTE cross reference I have is in storage, and is about

1.25" thick, with millions of OEM part numbers.

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You can't have a sense of humor, if you have no sense.

Jamie

Sigh. "Maynard A Philbrook Jr." strikes again. That doesn't answer either of his questions. It doesn't list any of the transistors it replaces, and it doesn't provide a spice model. There isn't enough information in that data sheet to create n acceptable spice model.

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You can't have a sense of humor, if you have no sense.

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You can't have a sense of humor, if you have no sense.

...

Er, wasnt' it the NTE10, last time.

The NTE199 is a whole different kettle of fish. Digging out the Xref book, it crosses to at least 85 numbers in the 2sc range, with a couple of more in the BCxxx range, and I didn't look at the 2N range. And a lot of those parts are sorted by gain, with the '199 for the higher gain ones, and the lower gain ones with another NTE number.

If an exact match is important, it's got a PNP complement, the NTE234. So finding a Japanese transistor characteristics chart and looking for complmentary parts that both have a hfe > 400, an Ft of 80-90 MHz and only good for 50-100 milliamps might find an exact match.

Remembering various parts mentioned in s.e.repair and searching on google, perhaps the 2sc733 or 2sc828.

If I were homebrewing from scratch, I'd think something like the BC550C would be cheaper than the $1 or so the NTE parts cost.

Mark Zenier snipped-for-privacy@eskimo.com Googleproofaddress(account:mzenier provider:eskimo domain:com)

MY GOD! THANK YOU! And you are right, it was the NTE10 last time, which is why I can't find it in the Google archives. Damn, I'm an idiot. But thank you so much for your help. I'm going to print this post and hang on my workstation. Man, I had just about given up. Can you tell me what cross you are using to find all of this? I need to get my own copy...

Dave

yes it's this.

5 ghz cut off small npn transistor.. usable up around 1 ghz. depending in how much gain you want.

P.S. This type of transistors like generate little parasitic noise due to their high frequency nature. I guess if you have a circuit to go by, that problem most like has been considered.

There are many Ghz transistors out there with industrial numbers on them. Jamie

I'm enough of a packrat that I've still got the NTE _1990-1991 Technical Guide and Cross Reference_. (And a magnifying glass. And about a dozen boxes of databooks from about 1975 to 1995. Alas, few Japanese ones.)

They were cheap or free at an NTE dealer (depending on how much business you did there), published every year or two. (The ECG and SK lines also had them, when they still existed). Cheap newsprint, about the same size as a Sear's catalog. Maybe they're still published. A ham swapmeet, EBay, or even a local (or university) library reference section could have one.

Mark Zenier snipped-for-privacy@eskimo.com Googleproofaddress(account:mzenier provider:eskimo domain:com)

Well, duh, that doesn't get you a SPICE model. There's a lot of projects out there in the hobby world (real and virtual) that use NTE parts, because they're available.

In this case, it was the 2SC2671, as I remember. Going through the book backwards and finding the real part is a bit of a sport here.

The goal here is to find the original part that the NTE is a replacement for, because you can't get a good SPICE model and a detailed datasheet from NTE/ECG/SK/HEP. (Well, ECG did publish databooks for the ICs that were reprints of the originals with the numbers filed off, but that was mostly TV jungle chips and audio amps and the more complex stuff).

And, (unless it's really gone obselete and nobody but NTE has stock), you can get it a whole lot cheaper. The whole universal replacement business is based on marking up the part, a lot. With the cost of stocking up for a last time buy (or getting your own run of parts made), a couple of level of distribution (in the old days of neighborhood electronics stores) , and markup for the retailer for having sit on the peg on the wall for years, these parts are going to cost up to 16 times what you could get the same stuff for in bulk from a franchised distributor.

If you can get them at all. A lot of these are japanese parts not sold in North America through normal channels.

Mark Zenier snipped-for-privacy@eskimo.com Googleproofaddress(account:mzenier provider:eskimo domain:com)

I remember getting a free HEP catalog about 1973. It was good since it was a useful way to look up parts to get a general idea, at a time when I didn't have many databooks. Even later, that sort of book continued to be useful since it beat looking through all kinds of different books to find the device.

I don't think I ever bought HEP parts, I knew from the start they were expensive. Sam's had a transistor substition guide, but you had to pay real money for it, and there were lots of other books to buy first.

The SK guide never seemed particularly useful, it seemed like a smaller set of devices. Of course HEP started small, the first replacement guide was much thinner than the second one I got a few years later, and I remember often coming up blank for a lot of devices in the first HEP guide I had. Radio Shack had a replacement line too, not sure if it was their own making or they just took a subset of someone else's line. I got the replacement guide cheap, but it was nver particularly useful.

I got an ECG replacement guide quite late, I don't know what happened then. And then later found a later edition in some odd place like a used book sale, or someone's recycling bin. They were much better than the HEP line at its best.

I still have them, and the databooks I collected. It used to be so cmmon for people to ask about old devices in the newsgroups, it's been some time that it was common now.

I think ECG, or rather NTE now, gave up on the paper guide. They did issue a CD for a while, but I think now you're stuck with the webpage that has a means of doing a search. The times I've tried, I've not been that successful, so maybe the line has been cut back. That's why it's still useful to keep old paper books.

Of course, if someone is taking parts out of an existing piece of equipment, it's often worth keeping the equipment intact, or at least tracing out the circuit. Something like the ECG guide might have pinouts for ICs, but what to do with them is not always clear. A working circuit provides a sample circuit, and if you're going to use an IC in that way, might as well keep it intact, often the parts surrounding it are exactly what you need.

Michael

The first SK cross reference I used was a medium sized wall chart, in the mid '60s. The other lines came out later. They were intended to let a shop keep a small stock of semiconductors on hand to do the most common repairs. At that time, they were hard to source if you weren't a factory approved servicer. Paying more to get it right away allowed more completed repairs. The OEM transistors we stocked in the early '70s usually took over 90 days for delivery.

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You can't have a sense of humor, if you have no sense.

OTOH, I just purchased (to replace a water damaged copy!) a brand new paper NTE cross guide from Parts Express (or was it MCM? Forget offhand.)

I prefer the CD for most usage, but the paper is hard to beat for notes in the margin.

RwP