Is it possible that the LDG is using its own internal SWR bridge and that
might not be in agreement with the TT? IOW the LDG 'thinks' it has nearly a
1:1 match, but the TT is showing something different? It wouldn't be the
first time two SWR bridges showed different readings!
Ron
N6AHA
----- Original Message -----
From: "Randy K4QO" <k4qo@earthlink.net>
To: <tentec@contesting.com>
Sent: Monday, February 13, 2006 7:50 PM
Subject: [TenTec] LDG tuner install/first impressions
>
>
> I spent most of today (Sunday) removing the TenTec supplied auto-tuner
> and putting the LDG in its place. ( a couple of times actually - not
> fun!) For now, I'm keeping the TenTec model. Here's why...
>
> Basically, I like the way the TenTec one works now. When the TT one
> tunes and you don't like that it came up with 1.8 or 1.4:1 or whatever,
> you can re-tune with two pushes - one to turn off the tuner and then
> again to bring it back on and do a "re-tune". The TT tuner seems to
> "start" at the last tune setting and it usually improves on the match.
>
> The LDG model does not allow this. Whatever you get from the tune cycle
> is what you get - no refinements- if you invoke another tune it either
> will select a memory one (like the last one it just did) or if you force
> it to fully re-tune it starts from scratch and then stops where it did
> before.
>
> Another reason for keeping the TT model for now is sort of alluded to in
> the last paragraph. It doesn't match as well as the TT version. Using
> the same antenna for a run through all the bands, the TT would give an
> average of 1.1:1 (on the first tune) while the LDG model only got to
> 1.4:1 on 3 bands and most bands were 1.8:1 or as much as 2.0:1 on 10
> meters. I use a 500 foot loop at 50 feet fed with 450 window line. The
> TT model has no trouble with it. I'm pretty sure the LDG match would
> improve if it would allow a "refine" second tune, starting from the last
> known match. But it didn't "first tune" as well as the TT model. I
> thought my other LDG tuners did better on the first stab at a match, but
> its been a while since I used them.
>
> I'm an LDG fan as I have a few of their tuners for other situations.
> This one missed the mark for me. Perhaps they will read this and look
> at modifying the firmware to allow the "refine" tune. 200 memories
> aren't useful if they are all at 1.8:1 or so.
>
> In looking closer at the TT model, I noticed a lot more circuitry -
> perhaps mostly unused. Not sure. BUT, it looks like it is capable of
> receiving band information via a communication port on the board that is
> presently not hooked up. Wouldn't it be great if TT was able to someday
> have the tuner remember tune settings per band so that when you change
> bands with the tuner enabled, it would automatically change the tuner
> settings. (oh yeah..., like my $800 K2!)
>
> One the topic of hardware, the LDG model has 7 inductors and the TT
> model has eight. The TT model has a lot more (tuning) capacitors but I
> suspect they are paralleled to make the values they need. Not sure but I
> think they both have at least eight actual tuning capacitor values. I'm
> looking for the schematic of the TT tuner if anyone knows where to find
> it.
>
> Installation note: If you already have the TT tuner installed, the LDG
> directions ignore this. I found myself wishing they had allowed for
> guys like me who already have wires run throughout the radio and only
> need to change the board. Some female jacks on their tuner board (just
> like the TT one!) would have been really handy. As it comes from LDG,
> they solder the In and Out cables to the board and force you to replace
> the TT ones. A real pain and waste of effort.
>
> And while I'm whining about the install - some kind of mating connector
> for the control wires coming from the front panel would be nice too. I
> fabricated a way to mate them so I wouldn't have to dig into the front
> panel. Bottom line: Looks like the LDG tuner is not ready for prime
> time but not far from being all it is supposed to be. I'm keeping the
> TT model installed for now.
>
> (Epilog: I had posted this on the Orion reflector and there enusued a
> "whats wrong with 1.8:1?" kind of exchange. Whats wrong with it is I'm
> used to seeing (for bad or for worse) 1.0:1's with the TenTec tuner. I
> didn't expect to go backwards with the new tuner. I'm investigating
> some technical aspects to determine why the matches aren't as good.
> Until then its on the bench and not in the radio.)
>
> 73,
> Randy
> K4QO
>
>
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>
>
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