In certain cases, for 160M and sometimes 75M, the external cap needs to be
greater than the 1000 pf item provided. I've found that up to 2700 pf might
be needed in some cases. This tuner will usually match any load Z, any
phase angle between 10 ohms and 3000 ohms.
FYI - This series of tuners will have some of the lowest loss figures of any
on the market today. Typically less than 1 dB. Plus, being a L network,
unlike the T networks tuners, there is only one set of adjustment parameters
that produce a proper match.
73
Bob, K4TAX
----- Original Message -----
From: "Jim Brown K9YC" <k9yc@audiosystemsgroup.com>
To: "Tony Dangelo" <tony@ammocomp.com>; <tentec@contesting.com>
Sent: Tuesday, January 22, 2008 5:45 PM
Subject: Re: [TenTec] Antenna Tuner 238
> On Tue, 22 Jan 2008 17:26:20 -0500, Tony Dangelo wrote:
>
>>Am I missing something?
>
> The 229 and 238 (essentially the same tuner in a different color
> case and with their dial cords wound in the opposite directions) are
> really excellent tuners, and can be tuned to match almost any
> reasonable antenna. Sometimes, if the antenna is far from 50 ohms
> resistive, it can take a while to find the match. And if it's TOO
> far from 50 ohms, you may not be able to match it. I've had this
> happen when the antenna is a half wave vertical on 80 or 160, which
> is a VERY high impedance.
>
> TenTec supplies a capacitor that you can connect between two
> terminals on the back panel to extend the tuning range of the tuner
> on 80 and 160. That solves the problem I described above.
>
> 73,
>
> Jim Brown K9YC
>
>
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> TenTec@contesting.com
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>
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