I had a horrible possible spur discovery last night just before bed. If it wasn't already a kick in the nuts to have to admit defeat with the FM initiative of more field strength due to the facts that presented itself during intense study and a reality check I found out that my SainSonic AX-05B may not be as nice as I thought it was. Imagine that why is that not a surprise when it rains it pours as they say. Well just before bed and I noticed a slight hum on my TV 3 feet away from the TX. At first I thought it was the mini refrigerator I have in my room for my cans of pop. I turned off the cable box and heard the hum. Shut down my Radio station and at last turned off my transmitter after a whole daytime show lasting till 4AM. Hey hum gone. Oh oh Huston, we have a problem. Danger Will Robinson, Danger! I turned the transmitter back on at the high power setting. Hum comes back. What a kick in the pants. I'm glad this was discovered now instead of a NOUO from the FCC. I remember telling you folks that at high power and at 10 feet it would bleed a boom box but go outside and its gone and everything is normal. Scratching my head and reading about the CZH-15A it all rang in my head too clear. This thing could be doing what the 15 watt CZH-15A done causing spurs on the lower frequencies below the FM band. I decided to switch to low power. Now I fired it up and NO HUM! Problem solved! Yes that is solved I can deal with that but No signal outside my house that is use able for reception not even on the porch. If I am outside and follow the contour of the house I get signal. And get this IT FOLLOWS THE POWER LINES!! What carrier current FM? What did SainSonic do? It has to be inches from the lines but if I walk under the power lines I hear my station till next door as long as I'm outside with the boom box. Does this transmitter feed RF into the lines either accidentally or on purpose I don't know. Is the signal use able inside people's houses? Don't know. I'll need to see when someone buys that empty house next door if they plug their FM Radio in and tune to 87.9 Mhz what will happen. Here I'm talking about carrier current FM and I already have a transmitter doing it and God knows what else. Damn the harmonics or lower spurs arent interfering at low power but imagine what damage this thing could have caused 10 feet away to the neighbor's house in front of me. Not a darn bit cool (I'm trying to keep it clean here as I slam my fist against the desk in anger at a mess I could have caused. I wish I had a spectrum analyzer just so I could see what this thing is up to. That transmitter should be tested by someone just for the sake of part 15ers like me who invest in transmitters when low on cash. I guess I should really had just bought a Talking House AM transmitter with that $54 but I'd always be wanting to test FM not knowing. Folks I know now. Save your hard earned money and if you want FM get something different. Even if you have to buy a scoche and if you have extra wire on it your on your own for you may be over the 250 uVm @ 3 meter rule. We will know if someone has a Patomac FIM 71 to test. I guess Carl can tell us did you get bleed from the Scoche you had keep forgetting the model number. And if my memory serves me right it traveled further than the low power of the SainSonic AX-05B and none of the damn spurs either. Even the Maxell P-13 looked good in review but can only transmit on a few channels. I'd want to modify it to have a digital display. What are your thoughts?
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