I'd expect a certain amount of downtilt when using the Marine Band antenna down on the 2-meter band.  This may or may not be problematic, depending upon height of antenna and surrounding terrain.   Matter of fact, if at the top of a hill or mountain and needing to communicate down into valleys locally, it might perform a tad bit better. 

Marketing history shows that big success usually comes from breaking paradigms, not following them. 

The 3rd overtone osc. loves - read demands - high impedance input, no? 

Actually, I have. 

Investigating the original papers on the subject, I found out that the two physicists who discovered this whole process to be based on "Graphene" -- a form of Carbon. 

Further reading uncovered that these two fellow discovered the capacitive storage situation quite by accident, but had their Serendippity glasses on at the time. 

They were cleaning ordinary pencil graphite, carbon, if you will, from some stones for some reason, and were using transparent tape to do that. 

The carbon would adhere to the sticky side of the tape. 

Apparently one of them looked at a piece of the tape that was so covered on the sticky side with the carbon rubbed from the stone and realized they had a flexible, thin, layer of something conductive adhered to something dielectric. 

And anyone who has a bit of curiousity coupled with the love of hands on experimentation can use those same tools to check out the Graphene capacitor situation, rather easily, I might add. 

To my way of thinking, whether or not a discovery comes to market fruition isn't necessarily the goal, or at least not the only goal. 

But I do not view everything in this world to be market driven. 


73

Remember that they can also be used at lower frequencies, or even as switch provided the DC parameters are not exceeded. 

We used to have a drawer in the shop's transistor storage that contained some rather nice but house branded and ID'd NPN's that one of the techs wrote over the drawer label, "Magic NPN substitute for ANYTHING!" -- and indeed, it often seemed to be the case. 

And a plastic bag that contained over a thousand of these little blue colored glass diodes that only had the Motorola M on them and the Cathode band.  Those darn things were fast, could handle the current of just about any circuit that had a glass silicon diode in it, and from that day on we never spent money on 1N148, 1N945, etc. glass diodes when needing one for a repair.  One of us once stuck 4 of those little blue glass diodes in a bridge after a power transformer in an aprox 1A low voltage supply - and they worked.  Didn't leave 'em in there, though, it was just to see...

5.000 count does seem a bit extreme, you might consider starting some sort of giveaway campaign where a ham who sends you a modest amount to cover shipping and handling might receive a bag of 100 or something like that.  Or that might be more trouble than you want to deal with, which is understandable as well. 

So what it may mean is that Tanakasan will never run out of small signal PNPs in this lifetime.


73

Yes, that tuner is not designed to work at 2 meters at all. 

Well, the Gun Free Zones have worked out so well now, haven't they? 

I think Ron White has something pertinent to say at this point: 

https://www.youtube.com/watch?v=fL6wbsGx9qw

Yes, Amidon is another good source that I would recommend without reserve. 

About CATALOGS --

The aspiring electronics experimenter can learn quite a bit from ordering and perusing various electronics parts catalogs. 

Many of them have a lot more than just parts and prices in them, they also have good reference information, charts, graphs, guides on how to select a component for a particular task, formulas, sometimes even recommended "cookbook" circuit data as well. 

And the modern "paperless office" situation works well also, the downloading of not only the main catalogs, but flyers, addendums, datasheets, even projects using a company's products is fast and easy to do. 

Pouring over the catalogs is what separates the geeks from the boys. 

Good Reading,


73

How did the bipolar 2N2222 get into this conversation about an FET oscillator? 

Why does any new kit have to be tube driven? 

A modern Heathkit, IMO, should incorporate the same design scenario that the original Heathkit engineers and designers used, which was to first ascertain parts availability at good purchase prices and then set out to design the intended gadget around those available parts, only moving to "specified" and more expensive components when absolutely necessary, and affordable. 

Back in those days, it meant that Heath could take good advantage of the postwar situation where entire boxcar loads of electronic components could be purchased on the surplus market for pennies on the dollar. 

While we don't have that kind of postwar effluence around today, there are other sources where the savvy designer and parts procurement engineer could exercise the same kind of thing. 

Consider the Cellphone, the PC, the Flatscreen, etc. markets and the components readily available from such. 

And it would be a dynamite chance for a new company to introduce more hams and electronics experimenters to the ease of manually assembling with Surface Mount components as well. 

The fear of SMT, the horror stories that are not even close to being true, the protestations of those who don't really know because they have never actually tried, multiplied by the self-described elites who make wholly untrue claims about equipment needs, methods and such concerning the manual assembly of SMT components onto a board can only be described as a basic prejudice and has no basis in real fact. 

Producing kits with the kind of manuals that Heathkit was known for today would be an easier task than it was back in the day, too, considering all the pc digital publishing tools we have today, the digital cameras, the photoshopping abilities, etc.  -- And consider a Heathkit that also came with DVD disk movies showing actual people demonstrating actual assemblies, etc. 

And that could lead to a dynamite step-by-step way of teaching folks that Surface Mount assembly is indeed possible to due with rather standard manual soldering methods, as some of us have been actually doing since day one. 

Just something to think about...


73

Hi Gary, 


Do a bit of research into the Charge Pump circuit. 

Charge pump can be as simple as a single diode feeding into a capacitor tank, followed by buffer amp. 

That can be fed into an A-D on a uproc. 

The Charge Pump is good for yielding Peak Voltage of a signal, and can work to measure Current with proper design of feeding it. 

A bit of Integration in the negative feedback path of the buffer amp is a good idea.  typically one small cap of the right value to Integrate above the freq of interest. 


73

Hi again, Zoli,

Before doing anything else, have you cleaned and lubed the Squelch Control? 

Deoxit or any other good electronics tuner cleaner/lubricant, into the control and rotate the control several times from pin to pin. 

These radios are getting rather old, and I've been run around in circles due to the potentiometers drying out.  Even if the control does not sound scratchy, the center wiper brush can sometimes create all sorts of problems, much like you describe.


73

The cellphone world has given us a plethora of smt chips 'n stuff that can go up pretty high...

Fair-Right Products has been my main source for all things ferrite, including information. 

http://www.fair-rite.com/newfair/index.htm

They've been at it for over 50 years.


73