Thursday, April 30, 2009

Excel Log Format

What is this signal?

Tom Seals, my brother-in-law and a SWL, sent me this wave file last nite.

Tom and I just talked again and he thinks it might be JT65.

Monday, April 27, 2009

Tuscaloosa AM Stations on 75m

AM stations in Tuscaloosa, Alabama broadcasting harmonics splatter across 75m.

Thursday, April 23, 2009

ATT Mystery Tone

We have two ATT lines coming into our house. Line 1 "appears" to be subject to some very strange form of RFI.

When I am operating on 75m (3.968) the person in the house will seem to "lose" the calling party for a short period of time--the line seems to go dead. During this period of silence, the calling party hears a steady tone lasting for no more than 2-3 seconds followed immediate by a chirp (almost like a FAX negotiation tone) and then connectivity is restored. Now the interesting part of the story...this happens several seconds AFTER I go key up...release the PTT.

I have recorded this phenomena for your listening enjoyment. This is the full testing protocol. This recording is just the resulting tone and chirp.

Wednesday, April 15, 2009

Thursday, April 9, 2009

Palstar AT1500CV Q-Test

An FT-1000mp Mark V was tuned to 7.2MHz. A Palstar AT1500CV was used to create a 1:1 match on a 75m/40m fan dipole. The frequency on the FT-1000 was then incremented in 10KHZ steps up to 7.3MHz. The following video shows the resulting SWR. Compare this to a similar Tentec trial which follows. I did not go down the band as in the Tentec trial.

Wednesday, April 8, 2009


Click on the image to enlarge

Yaesu IPO

A special thanks to WA5MLF for putting all of this in perspective!

Monday, April 6, 2009

Receiver Metrics--IMD & IP3

I think we really need to turn the IMD/IP3 presentation into a QST article.

Download the PPT presentation.

View the PPT presentation.

Thursday, April 2, 2009

W4UOA Portable


Support Line

Power Strip

DC Power Supply

Extra cable ties



A few last minute items!