Help making DIY balun from DBT LogPeriodic Antenna to 490-700mHz preamp

[Paul Price]

FTG.
The Swedish transponders operate on different freqs then local.

I have received my ordered 22-dB ant preamp with GTE/4G filter and it mounted 6 cm from the rear end of my existing antenna and it boosted reception of a single Skåne Chan4 HD to allow reception some days very clearly for most hours, yet for some hours on some days the receiver shows no signal.

The receiver's built in Advance System Info shows signal strength and quality and the signal strength is 100% and the quality varies second by second from in 3% steps 0 to 23%, yet 90% of the time signal strength is greater than 2%  Yet there is no signal at all from SV1 SV1-HD, SV2, SV2-HD, SV24 Cultural channel.
I last allowed a channel scan some two-weeks ago and I'm now wondering if these channels, which are in the list of active channels, is still valid. 
Catch 22:  If I allow another scan, the receiver could possibly delete the channels I want from the active list, that means I cannot set the receiver at all to show a channel not registered by a scan, so I cannot set the receiver to a channel of interest and cannot see any signal strength graph to try to find the best position to point the antenna and I have no signal to work with.

The odd thing is the TV4 HD Scåne transponder is much further away then the Målmo transponder!

[Paul Price]

Plenari,

The antenna picture you have posted looks very promising.

I would really like to know what it cost and the length and spacing of each element!.  I bought a 2 meter long 3 boom mushroom yagi that didn't allow any reception of Swedish channels, but  I have all the pieces of it stacked up in my closet. If I knew the measurements of your antenna I could fairly easily clone the antenna you say allows reception of stations 160kM  away!

[pienari]

That Iskra antenna i found from metal scrap,it is not good because there is no LTE filter.
I can see LTE800 signal for my dvb-t signal analyzer, LTE800 signal is stronger then any DVB-T.

Manufactur claims gain 8dbi , i think gain is lower.

Most of the yagis are too high freqs .. ch43-69 .

Edit..
I made more tests.
Iskra P-20WF is better in low channels 21-37.
CH45 signal was weak now so i compared 1 of my yagis.
Yagi was superb in high freqs but ch21 signal was weak.

Today i installed Iskra preamp to my long Iskra vhf/uhf  Logperoidic antenna .
Gain is a bit better to ch21 but much better in ch45.