 photo 1 |
 photo 2 |
In the Radcom October 1985 there was an article entitled An Improved Z-Match ASTU by Louis Varney G5RV. This proposed some radical changes to the original Z match design and involved some rather complicated switching. Also it did not include the 160 metre band. The design did not appeal to me but what did take my attention was the significant reduction in the diameter of the coils. I checked the inductance of the coils in the original version and then made this Z match with coils of reduced diameter but with the same inductance. However, as can be seen in photo 4, the 80 metre tuning and coupling coils still had spaced turns which made them at bit long. By the way, this unit was built into a scrap psu case with holes all over the place. The front of the case became the back, and the back became the front with a piece of scrap aluminium for an overlay just to make it look presentable. The unit tunes all bands 160 to 10 metres. Maximum power handing is 100 watts. |
|
 photo 3 |
|
|
|
