Whichever power level you need...
But clean ones are very rare. They are all 50 or 60 years old now and many
have been abused.
73
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Al Gulseth
Sent: Monday, July 18, 2016 7:19 PM
To: tentec@contesting.com
Cc: rick@dj0ip.de
Subject: Re: [TenTec] OT: Question to the group
Rick,
Just to clarify here - when you say "if you can find a good JVM, buy it" - are
you referring to the 275W or the KW version, or both?
TNX/73, Al
On Mon July 18 2016 11:00:54 am rick@dj0ip.de wrote:
> FULL AGREEMENT GARY, EVERY WORD.
>
> RECOMMENDATION TO ALL: if you can find a good JVM, buy it. You'll
> never regret it.
>
> WARNING: More than half of the JVM's I have seen at hamfests were
> garbage on the inside and not worth much more than the scrap metal
> value of the box. BEFORE YOU BUY, remove the 30 or so screws and take
> a look and the inner components.
>
> Tip: Most people selling these won't want you to open them. When I
> bought my last one, I offered the OM $10 to allow me to open it up.
> Said if it is clean, I will buy it and the $10 goes towards the
> purchase. If not clean, I won't buy it but he can keep the $10. If
> he still won't let you open it, DON'T BUY IT. It probably has a
> melted coil form (the larger coil) and is no longer balanced.
>
> 73
> Rick, DJ0IP
>
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Gary
> J FollettDukes HiFi Sent: Monday, July 18, 2016 4:13 PM
> To: wb5jnc@centurytel.net; Discussion of Ten-Tec Equipment
> Cc: Paul Christensen
> Subject: Re: [TenTec] OT: Question to the group
>
> Antennas and tuners are fun. They are about the last bastion in which
> hams can still perform meaningful experiments and produce publishable results.
>
> Radios have simply gotten complex to the point at which everyday hams
> can no longer do much with them but plug them in and turn the knobs
> (or press the keys).
>
> SMD’s and SDR’s only serve to take hams farther from being involved
> with their radios’s operational theory.
>
> Antennas (and tuners), on the other hand, offer an opportunity for one
> to perform mathematical modeling to predict designs, optimize them,
> build them and finally test them.
>
> Paul and Rick both have shown extensive knowledge, both in terms of
> modeling and practical construction. Their input is very valuable to
> this discussion.
>
> I do not yet have the time to go into those aspects of antennas and
> tuners since I am still spending my time doing lab science on chemical
> sensors and flame detectors.
>
> Therefore, my expressed opinions on the topic are based only upon my
> own practical experiences, some of those being over 40 years ago.
>
> Thanks for an interesting discussion in which I received more than I gave.
>
> I admit to having overstated the EFJ Matchbox in terms of being the
> “best ever”, but it is better than most I have seen lately, and t
> worked in every application in which I tried it. Plus, it never arced on me.
>
> It’s kind of like a restaurant owner saying "Our restaurant has the
> best burger anywhere”. Really? Have they tried all of them and taken
> into account that different people have different preferences in burgers?
>
> Gary
>
> W0DVN
>
> PS: Does anyone know why Ten ten chose to allow operation of the
> internal auto tuner in the Orion only on antenna 1 output? Everybody
> else seems to have figured out long ago how to do the antenna
> switching AFTER the tuner so that it would work on both antenna outputs.
>
>
> PPS: The EFJ Matchbox was a real pain to repair if the band switch
> seized up (which it frequently did). The level of disassembly required
> to remove the shaft from the switch, clean and lubricate it, was far
> disproportionate compared with other tuners. It is nice to see that
> Nye Viking carried this tradition forward with the MB5 VI series. What
> a masterpiece of design in terms of making parts nearly impossible to
> remove for repair! Add that to the fact that there were several
> designs for the directional coupler, only one of which was documented,
> and you have good reason to make parts mules out of some of them.
>
> > On Jul 18, 2016, at 8:38 AM, Al Gulseth <wb5jnc@centurytel.net> wrote:
> >
> > Paul,
> >
> > Why the need for a rotating turret? Wouldn't switching taps
> > accomplish the same thing? Cliplead taps on the coil have been a
> > staple of link coupled systems since the early days of ham radio,
> > and it seems to me that one could locate the optimum taps for each
> > band and then use relays to switch them. Doing it that way shouldn't
> > be any more complex than a typical autotuner is.
> >
> > 73, Al
> >
> > On Mon July 18 2016 6:47:02 am Paul Christensen wrote:
> >> ...
> >> A remote-controlled link tuner would by my Holy Grail, but the
> >> mechanical complexities start getting in the way of improved
> >> efficiency. To do it right would require separate link coils moved
> >> on a rotating turret. ...
> >>
> >> Paul, W9AC
> >>
> >> _______________________________________________
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> >
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>
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