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sounds like a BLT .Do a google search you should find some info.
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#2
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sounds like a BLT .Do a google search you should find some info.
The Norcal BLT (which is what I believe you're referring to) is a Z-match type of tuner. It uses a single toroid to create a coupling link between the unbalanced input and the balanced output. The BLT's toroid is wound with a single primary (having a single fixed tap), and a pair of secondaries for low- and high-impedance loads. It does _not_ have the sort of multiply-tapped-and-switched coil architecture that the original poster alluded to - these are usually used in unbalanced-configuration T and L tuners. The tuning is done with the two capacitors (a series input cap, and a cap which shunts the primary toroid winding), and via a DPDT switch to select the appropriate secondary winding. I don't know whether the OP's components and kit were originally intended for a multiply-tapped-inductor T tuner, or for a Z-match such as the BLT, but it sounds likely that they could probably be adapted to either (possibly with the addition of a few extra junkbox components). I built a Norcal BLT a few months ago, and I've been quite happy with it... it's a nice little QRP design especially when modded to support coax-fed unbalanced antennas (add one BNC jack and one SPST switch). The lack of multiple inductor taps and a tap-selection switch is a definite plus, convenience-wise. It seems to tune my tri-wire fan dipole to off-resonant frequencies just as effectively as my big QRO tuner (based on the Ultimate Transmatch design, according to the guy who built it). -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
#3
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sounds like a BLT .Do a google search you should find some info.
The Norcal BLT (which is what I believe you're referring to) is a Z-match type of tuner. It uses a single toroid to create a coupling link between the unbalanced input and the balanced output. The BLT's toroid is wound with a single primary (having a single fixed tap), and a pair of secondaries for low- and high-impedance loads. It does _not_ have the sort of multiply-tapped-and-switched coil architecture that the original poster alluded to - these are usually used in unbalanced-configuration T and L tuners. The tuning is done with the two capacitors (a series input cap, and a cap which shunts the primary toroid winding), and via a DPDT switch to select the appropriate secondary winding. I don't know whether the OP's components and kit were originally intended for a multiply-tapped-inductor T tuner, or for a Z-match such as the BLT, but it sounds likely that they could probably be adapted to either (possibly with the addition of a few extra junkbox components). I built a Norcal BLT a few months ago, and I've been quite happy with it... it's a nice little QRP design especially when modded to support coax-fed unbalanced antennas (add one BNC jack and one SPST switch). The lack of multiple inductor taps and a tap-selection switch is a definite plus, convenience-wise. It seems to tune my tri-wire fan dipole to off-resonant frequencies just as effectively as my big QRO tuner (based on the Ultimate Transmatch design, according to the guy who built it). -- Dave Platt AE6EO Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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