1N34A diode

[K9FV]

Hello all, I desire a 1N34A germanium diode - those little buggers are hard to find locally. I am wishing to build a RF probe and read that is the best diode for this use. The instructions say a 1N458A will work also, but I'm not able to find either of those locally - and my junk..... ahhh, treasure chest does not contain either part. The 1N34A has a forward voltage of 0.3 while the 1N458A is 1 volt - that makes the 1N34A better.... doesn't it?

Digi-Key has the 1N458A in stock, BUT only in min of 2,000 and I don't need that many. Mouser has both in stock, but the $6 shipping makes it pretty expensive. Radio Shack does not list either diode on the web catalog. Perhaps a substitute for either that RS might have?

Any other suggestions for local? I can use thru-hole or SMD version.

73 de Ken H.

[K8ERV]

Sure I can find one, will send in a few days.

TOM K8ERV Montrose Colo

[K9FV]

You a good man Tom - my address on QRZ is good.... I'll be HAPPY to send you back money for postage and cost of diode.

73 de Ken h.

[W4HAY]

If you need more stuff like that, The XTAL Set Society (http://www.midnightscience.com/catalog5.html) has a few items.

[K7FE]

Hello all, I desire a 1N34A germanium diode - those little buggers are hard to find locally. I am wishing to build a RF probe and read that is the best diode for this use. The instructions say a 1N458A will work also, but I'm not able to find either of those locally - and my junk..... ahhh, treasure chest does not contain either part. The 1N34A has a forward voltage of 0.3 while the 1N458A is 1 volt - that makes the 1N34A better.... doesn't it?

Digi-Key has the 1N458A in stock, BUT only in min of 2,000 and I don't need that many. Mouser has both in stock, but the $6 shipping makes it pretty expensive. Radio Shack does not list either diode on the web catalog. Perhaps a substitute for either that RS might have?

Any other suggestions for local? I can use thru-hole or SMD version.

73 de Ken H.

You do not need a 1N34 germanium diode for your RF probe.

The reasons for using a germanium RF diode have been mostly negated since the development and availability of Schottky diodes. The forward voltage drop is only about 0.1 volt higher (or less) for the Schottky and the newer Schottky is much more rugged than the old Germanium types. That means, you will not be as likely to damage the Schottky when used in your probe.

Many companies make them and they are used as balanced mixers in almost every modern amateur transceiver.

If you have an application other than a simple RF probe and you wish a lower Vf (forward voltage drop), just bias the diode slightly to obtain Vf's closer to zero.

73,
Terry, K7FE

[K8ERV]

You a good man Tom -



You know that , I know that, my wife knows that, but sure hard to convince that dog.

At the moment I can't find the 34, tho have seen it recently. SOP. I found a 56a with similar ratings and construction, will send it if I can't find the 34.

No charge, many have helped me.

TOM K8ERV Montrose Colo

[KL7AJ]

Hello all, I desire a 1N34A germanium diode - those little buggers are hard to find locally. I am wishing to build a RF probe and read that is the best diode for this use. The instructions say a 1N458A will work also, but I'm not able to find either of those locally - and my junk..... ahhh, treasure chest does not contain either part. The 1N34A has a forward voltage of 0.3 while the 1N458A is 1 volt - that makes the 1N34A better.... doesn't it?

Digi-Key has the 1N458A in stock, BUT only in min of 2,000 and I don't need that many. Mouser has both in stock, but the $6 shipping makes it pretty expensive. Radio Shack does not list either diode on the web catalog. Perhaps a substitute for either that RS might have?

Any other suggestions for local? I can use thru-hole or SMD version.

73 de Ken H.


Yah....these things used to grow on trees. If you can't find any, you can go the more expensive route and buy a schottkey diode. Or you actually apply a little bias to a sillycone diode to make it...uh...er....biased

[KB7BX]

Ken,

I am holding 3 Ea. in my hand. If you still want thenm I can put them in the mail tomorrow.

Jerry.

[K9FV]

Thanks for all the postive response - I just hope I can return the favor sometime.

Jerry, I am good on QRZ.

THANKS a whole bunch ya'll (yea, I'm from the south)

73 de Ken H.

[KD8DEY]

Built mine on a terminal strip from Radio Shack, Used a cigar tube to mount it in and wired with an old extra set of probe wires :D if you have an old portable radio in the parts bin you will probably find a couple of them in there. or maybe even in an old CB. You can usually Identify it as the piece dicconnected on one end (breaking the AF-AGC) :D

[K8ERV]

Glad Jerry found some, think I will keep my 56a, the only one I have.

TOM K8ERV Montrose Colo

[K9FV]

Thanks for the offer Tom - Jerry will send it. Thanks so much to both of ya'll - just hope I can return the favor sometime.

73 de Ken H.

[K8ERV]

Thanks for the offer Tom - Jerry will send it. Thanks so much to both of ya'll - just hope I can return the favor sometime.

73 de Ken H.

On second thot, I will trade my 1N56A for Vanna----

TOM K8ERV Montrose Colo

[WY6K]

Can't remember where I got mine, but 1N34As are readily available in small quantities at reasonable prices. I've bought several batches of 10 or so in the last couple of years.

Maybe the crystal set guy?

These are also the kinds of things I tag on the top of other orders from Mouser - just to build up the parts bins without shipping costs. Sort of like "earmarks". :-)

[VK2TIL]

Futurlec have them;

http://www.futurlec.com/cgi-bin/search/search.cgi

Fast service, good prices, nice people.

I do an order with them every few months; one arrived only a few days ago.

[K9FV]

That does look like a good vendor with good prices - did I read the shipping charges correct - $4 to the USA??? If so, then I'll be ordering some things from them.

73 de Ken H.

[VK2TIL]

Yes, you read it correctly.

I have found Futurlec very good.

[W9GB]

I desire a 1N34A germanium diode - those little buggers are hard to find locally.
Really? My local Radio Shack stores actually stock that part -- you have to look through the "parts drawers".
Don't ask the store's "cell phone staff" -- they are largely clueless in science, electronics or anything useful.

I usually keep 10 or so in my home parts bin.

Easily acquired through Mouser, and you can have in mailbox a couple of days later. I just ordered 100 of the current replacements for the 1N270.

w9gb

[K9FV]

Yes, you read it correctly.

I have found Futurlec very good.

Thanks again for the link - I just placed an order with them - for $4 total shipping/handling charges, they promise to have it delivered in a week.... Their prices seem better than Mouser - not as much inventory, but do seem to be a bit less, and funny, but shipping is less from half way 'round the world than from TX.

Perhaps I should have actually went to RS - I just checked the on-line catalog. There were several general purpose diodes listed, but NO 1N34 diodes - perhaps the local RS might have them. I just didn't think to check after 1N34 was not even listed on-line.

Thanks to all,

73 de Ken H.

[AB8RO]

That does look like a good vendor with good prices - did I read the shipping charges correct - $4 to the USA??? If so, then I'll be ordering some things from them.

73 de Ken H.

Just a warning with Futurlec. There shipping can be very slow. If parts are back-ordered they will often delay your entire order waiting for the back-ordered parts. They also are terrible communicators. Basically, if you need stuff sometime in the future from a week to a few months, they are ok to deal with and have good prices.

[VK2TIL]

I haven't had that experience with Futurlec.

I receive an acknowledgement e-mail that confirms the order, lists the items & prices and gives a reference number and a link to an order status page.

The next day I receive a "order sent" e-mail.

The goods arrive about 7-10 days later.

They made their first-ever mistake with my last order; I ordered 12 MHz crystals in HC-49/U cases and they sent 12 MHz crystals in HC-49/US cases. They stock both kinds under different numbers.

This would not usually matter; a 12 MHz crystal is a 12 MHz crystal.

But I particularly wanted the HC-49/U case; they tend to be better for filters.

I e-mailed Futurlec and explained why I wanted the HC-49/U devices; they replied within a day saying that replacements were on their way. They were most apologetic.

So I have the highest regard for their communications.

On a couple of occasions I have forgotten to include something in my order and e-mailed them next day; on one occasion they included the items in my order, on the other I was too late.

They were friendly and helpful on each occasion.

I have never had a "back-ordered" item; items I ordered have always been in stock. Any problems there would, I assume, show-up in the order confirmation e-mail they send.

[AB8RO]

I haven't had that experience with Futurlec.

I receive an acknowledgement e-mail that confirms the order, lists the items & prices and gives a reference number and a link to an order status page.

The next day I receive a "order sent" e-mail.

The goods arrive about 7-10 days later.

They made their first-ever mistake with my last order; I ordered 12 MHz crystals in HC-49/U cases and they sent 12 MHz crystals in HC-49/US cases. They stock both kinds under different numbers.

This would not usually matter; a 12 MHz crystal is a 12 MHz crystal.

But I particularly wanted the HC-49/U case; they tend to be better for filters.

I e-mailed Futurlec and explained why I wanted the HC-49/U devices; they replied within a day saying that replacements were on their way. They were most apologetic.

So I have the highest regard for their communications.

On a couple of occasions I have forgotten to include something in my order and e-mailed them next day; on one occasion they included the items in my order, on the other I was too late.

They were friendly and helpful on each occasion.

I have never had a "back-ordered" item; items I ordered have always been in stock. Any problems there would, I assume, show-up in the order confirmation e-mail they send.

Well, we have really different experiences. They held up an order for me because of backorder of a single item. When I told them to just cancel that item, send the remainder of the order, and refund the difference a several week ordeal of exchanged and confused ( on their part) emails began. They wouldn't respond at first and I suspect that they were hoping the back-ordered item would come in. They, in fact, lied in several emails about my order was absolutely going to ship on such and such a date.

They shouldn't have charged my card until they had the items ready to ship, in my opinion, but, given that they did they certainly should have been ready to complete my partial order and refund what they didn't have in stock.

When I asked them to replace the items that were back-ordered with different items they would not tell me which of the items that I wanted were also in back-ordered status. Really, that information should be on their web site.

So my experience is:

1) They are dishonest.
2) They are poor communicators.
3) They give poor customer service.
4) They are inflexible.

Maybe I was processed by a greedy salesperson who didn't want to partially refund my order but I'm definitely gun-shy.
It wasn't a very big order but it was close to $200.

[W8JI]

Hello all, I desire a 1N34A germanium diode - those little buggers are hard to find locally. I am wishing to build a RF probe and read that is the best diode for this use. The instructions say a 1N458A will work also, but I'm not able to find either of those locally - and my junk..... ahhh, treasure chest does not contain either part. The 1N34A has a forward voltage of 0.3 while the 1N458A is 1 volt - that makes the 1N34A better.... doesn't it?

Digi-Key has the 1N458A in stock, BUT only in min of 2,000 and I don't need that many. Mouser has both in stock, but the $6 shipping makes it pretty expensive. Radio Shack does not list either diode on the web catalog. Perhaps a substitute for either that RS might have?

Any other suggestions for local? I can use thru-hole or SMD version.

73 de Ken H.

For what you are doing, you can probably use any fast switching speed diode. I seriously doubt you would notice the change betwen a schottky, a gemanium like the 1N34, or a small signal silicon switching diode like a 1N916 or similar.


The reason is most meters like you are building have a detected voltage of several volts. Let's just say you have a 1 mA meter with a 10k limiting resistance. FS would be about 7 V RMS with a Schottky and maybe 7.3 RMS with a silicon switching diode. You would never notice that.


Now you might find the meter linearity would be off when you were down near 1/10th scale on the metering, but I doubt it would affect what you are trying to do.

73 Tom

[K9STH]

It depends on how little r.f. voltage that you are trying to detect. Probably in most cases the over 2 times the voltage drop in a small signal silicon diode like the 1N914 will not make much difference. However, if the signal level is pretty small then the difference between a silicon diode and a germanium diode will definitely be noticed. I have run into situations where the r.f. voltage was very low and using a silicon diode resulted in no meter movement whereas using a germanium diode got a reasonable meter reading.

For example, I have a Motorola TEK-7A r.f. volt meter that the maximum reading on the meter movement (lowest voltage range) is 0.5 volts r.f. Those meters have a habit of blowing the diode in the probe if you are not careful. If I replace the germanium diode with a silicon diode it takes considerably more r.f. to get a reading on the meter than normal when in the 0.5 volt maximum range. On the higher voltage ranges the difference is less and less noticeable as the maximum voltage indicated on the meter increases. But, when in the most sensitive position the difference in the diodes definitely makes a difference.

Glen, K9STH

[KB5RFT]

I carry these on my web-site in quantities of 10 for $2.99 and 25 for $4.69. Here's the address: http://www.myoldcamera.com/Diode%20Page%203.25.06.html

The shipping's reasonable under $20 and free on orders over $20. Please let me know if I can help you.

Best Regards,

David Gasaway
kb5rft

[K9FV]

I carry these on my web-site in quantities of 10 for $2.99 and 25 for $4.69. Here's the address: http://www.myoldcamera.com/Diode%20Page%203.25.06.html

The shipping's reasonable under $20 and free on orders over $20. Please let me know if I can help you.

Best Regards,

David Gasaway
kb5rft

Thanks for the link David - shipping sure is reasonable. I have bookmarked your site. I just placed an order with the Aussie link above and we'll see how that goes.

73 de Ken H>

[KC9KXW]

I have found 1N34A diodes at a local "CB" shop of all places, but the CB shop actually
has a lot of parts that you wouldn't find at Radio - cell phone, computer, toy - Shack.
Also they have very comperable pricing.

Good Luck and 73
Jim
KC9KXW

[K9FV]

Ken,

I am holding 3 Ea. in my hand. If you still want thenm I can put them in the mail tomorrow.

Jerry.

Got them Jerry - Thanks a whole bunch!! I have 10 on order from the Aussie place - once they get in I'll do my best to remember to send 3 back to you.

Thanks again - hams helping hams, good way to do it.

73 de Ken H.

[KI4HTR]

Dan's Small Parts & Kits has 1N34A diodes for a very reasonable price, along with a lot of other neat stuff.

The only drawback to dealing with Dan's is that all orders have to be check or M.O. sent via snail mail. Aside from that, I personally like his stuff & his prices. Check out his website at

http://www.danssmallpartsandkits.net/

[AE5JU]

Believe it or not...

www.1n34a.com (http://www.1n34a.com)

REALLY!

Scroll on down this parts page

http://www.1n34a.com/parts.htm

[WE5Q]

This is a pretty old thread, but wanted to point out a link to a RF Probe kit that I built and really like...

http://www.kk5na.com/kk5na_files/accuprobe.htm

VERY handy for RF electronics work.

Bill
WE5Q

[WE5Q]

Oppppssss.... No it's not... I was looking at the 'Join Date' LOL!

Anyway... the Accuprobe kit is a VERY handy item...

Bill
WE5Q

[W2KLM]

1N34A diodes are available from J-Tron Inc.

www.j-tron.com

Have Fun Building!
Jim
W2KLM

[KB5PN]

I've always found them at the local RatShack....as a previous poster mentione, you'll have to dig thru the parts drawers yourself, the staff doesn't know a diode from a pig with lipstick:D

[K2XC]

Ebay has alot of them low cost.:)

[K9FV]

Ebay has alot of them low cost.:)

item #110300139393 is a Set of 4 germanium green stripe NOS 1n34a diodes for $7 shipped - that's not all that cheap!! Almost $2 each for a 20 cent diode.

and this item 380026310147 is $11 shipped - and I think it's only a single diode.... not sure.

That doesn't sound all that "cheap"????

The http://www.futurlec.com/DiodesGen.shtml#General company has them for 5 cents each - then if you add the $4 shipping that makes them about 45 cents each. still best by over ebay!

73 de Ken H>

[W4CBJ]

There are several suppliers that sell these diodes for ten to nineteen cents each. Sure you can pay more for them. Shipping costs...another matter... 73 Joe W4CBJ