VHF June 2009

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From an e-mail from Rick to Dave.

Dave,

On the off-chance that I remember enough details to be useful, and before I forget them, I thought I would pass along what I heard from the various discussions.

6M

Consider a 31-33' boom antenna. AB-577 in the same position we used this time. LMR-400 feedline. No

2M

Two stacked yagis. Use the current power divider and phasing cables (which are relatively new). Add external switching to the preamp to protect it--being sure that when switched out, the preamp connectors are grounded. Use Omni with switch. Use 7/8 hardline. Need new jumper cables. Mount on Rohn 25 in the position now used by 222. Build and shake down station before next contest.

--Stu 14:00, 8 September 2009 (EDT) Fixed network drawing, repaired preamp and reworked sequencer. Not taking the omni.

222

Continue with current setup. Existing phasing cables are fine. Need new jumper from preamp to feedline with N connectors on both ends. Test jumper from preamp to divider. Use 7/8" hardline. No omni. Preamp switching over coax. Mount on AB-577 in the middle position west of the tent.

--Stu 14:01, 8 September 2009 (EDT) Lost W4DAV's 756, using WA0DYJ's TS2K, rig controls transverter and sequencer. WA0DYJ/W3LW tested jumper cables.

432

Use two stacked yagis. Leave off front director section to remove five elements. Larry will model shortened antennas to determine change in pattern, and to optimize vertical spacing. Stu1 will provide scans of antenna documentation to Larry so he can get the dimensions. Need new phasing cables. Reconnectorize 7/8" hardline for N connectors. Troubleshoot unusual receive audio in TS-2000. Rebuild driven element connections and hairpin match on antennas. No omni (for now). Preamp switching over coax. Need new jumper cables. Mount on Rohn 25 in current position. Replace mast with shortened mast of lighter weight.

--Stu 14:05, 8 September 2009 (EDT) W3LW/WA0DYJ tested cables and found some bad ones. W4AD/W4NF provided the 2 port combiner. W7IY modeled 16 and 24 element antennas using mid-night measurements from WA0DYJ. New stacking distance is 1M. Document scanned from KA4CKI says 5 feet. Antennas are Cushcraft 424B with K1FO driven elements.

General

Shorter antennas will broaden H-plane pattern, stacking will narrow E-plane pattern, both of which are desirable.

Need to scan antenna and tower configuration information for Stu2's wiki (Stu1). Possibly need to add sequencer configuration information to current station information--2M station sequencer required a setup parameter to switch amp properly. Need clearer configuration setup for 222 for setting up transverter offset. Label all jumpers.

--Stu 14:06, 8 September 2009 (EDT) Done.