Sorry to hear you are having trouble with the DB8e. They must have sent you a return without checking it. I have also heard that they are sending "warehouse specials" of the RCA TVPRAMP1R that have a DOA power supply. It's gotten to the point where I only order from them if I have no other choice. I would rather pay a little more to avoid the hassle of a return.
Recently I ordered three books for a book signing and paid extra for one day shipping, even though I'm a Prime member. They sent the books Printed Matter rate and missed the signing. Has Amazon gotten so big it isn't able to do good customer service anymore?
Was the DB8e aimed at 285 magnetic when you tried for KIRO 28? It has a very narrow beamwidth.
Did you try different locations in the attic for the DB8e? It is often necessary to hunt for a hot spot.
If there is a problem with the DB8e, Antennas Direct will make it good.
The only other thing I can think of is that the KIRO signal is coming down from the hill top. The 4-bay and 8-bay antennas have a narrow Vertical beamwidth because of the vertical stacking of the bays.
I have helped other people who also lived below a peak who had good success with tilting the front of their antenna up above the horizontal. They used an 91XG or an HDB91X, both of which have a tilt adjustment. The DB8e doesn't have a tilt adjustment; it would be a custom mod.
When I was doing antenna tests at one of my LOS test sites, I found it necessary to tilt the top of my DB4e back a little for MAX gain, even though I was aiming across a river at the towers.
