Have had this antenna for a few years. Originally installed it on the roof with a tripod and worked well picking up local and distant US stations to the south. We had the roof re-done, and it has been in storage for 2-3 years. Meanwhile I have been using an old VHF log periodic on a tower nearby with two HDHomeRuns, one connected to the log periodic for dx, the other on a 4-bay bow-tie pointing north for locals.

I finally got the HD7698P up in place of the log periodic up about 40' on the tower, new feedline and I had also replaced the Wingard balun (part of the antenna) since it looked to be corroded, didn't want trouble.

With the fancy Wingard antenna up on the tower I could only get CKY and KNRR (both within 30-40km. Nothing else! Seems dead as a door-nail! Would get better reception with a wet noodle. If I pointed it north right at Winnipeg I could scan in CBC but it blocks and fades out sporadically.

CKY is about 40km away antenna pointing right at it!:
Modulation Lock 8vsb
Signal Strength 61%
Signal Quality 90%
Symbol Quality 100%

Brought the tower down and put the log perodic back on and reception is back the way it was.

Checking the HD7698P I find no shorts in the vhf and uhf elements, good continuity between connected elements etc. Not finding anything wrong with the antenna itself. Nothing obvoius with the balun/circuit board. Seems electrically the same as the old one (continuity checks etc). I didn't check operation with the old balun (yet) though. Connection between UHD and VHF conductors at the balun seems fine.

I must be missing something... likely an issue too obvious for me to see...! Where else should I look? Any ideas appreciated.

Was looking forward to better UHF reception to the south.

You have to suspect the balun.

I also suspect the CB-8269 balun.

Winegard has a troubleshooting video. The idea is to check each section of the antenna with a conventional balun clipped to each set of wires for UHF and VHF.
How To Troubleshoot a Winegard Antenna Cartridge Housing
https://www.youtube.com/watch?v=TlQke5QYbng

I was wondering if some of the more knowledgeable members of the forum might be able to answer a question for me. I am interested in taking the feed from my antenna system and hooking it into a "box" which would then distribute my signal wirelessly to the various TV's and computers in my home. It sure would save a lot of time running coax all over the house which would be somewhere between difficult and impossible. Is there such a magic box? can I use an old computer modem? Just thinkin.....

Look into HDHomeRun Connect products.

Also check out Tablo and Recast. All require another "box" at each TV (i.e. Roku, Firestick) but accomplish what you want.

Ok, guess I'll have to pull the antenna down and do this check. Always have a few regular baluns around. It's a brand new CB-8269 but of course that doesn't mean it works. If nothing is grounded or shorted in the antenna harness or elements that would indicate only one likely possibility (unless the feedline or connector(s) is bad). Thank you for the information @rabbit73 and @Red Knave .
@fgt I use two HDHomeRuns and find they work relatively well. I use an Extend for nthe DX antenna (not working great right now) and a Connect for locals. It is likely a good idea to have ethernet with gigabit capability so there is lots of bandwidth headroom in your LAN even if they are 10-100 connections. I use one TV that uses wireless to connect to the LAN but it is 5.8HGz, I find the 2.4 wifi doesn't work as well. I am using a Uniquiti UniFi AP-AC-Mesh radio as an AP and it works really well. There are other options for network receivers that may be as good or even better, but these have worked well for me.