Thursday, December 10, 2009

HF radio (2)


Now that I connected the DDS3 vfo...I just found that 7 years without use made it to lost the registers.
It was bough in 2002 and since then it was only connect 2 or 3 times so it's natural this happened... the problem is the kit is no longer sold and the software came on a 3 1/4 diskette. I was lucky, managed to read the contents (Linux command "mcopy a: .") and saved the programing software to a new disk.... but there is another problem, the software runs in DOS, I don't use DOS for some 12 years and I don't use the other operating system that supports reading some DOS applications.
Linux has "dosemu" a dos emulator. I can now run the software but still didn't tryed to programe the equipment. DOS is not exactly the "shell" ins fact is "freedos".

The vfo for now is runing with an IF of 14 Mhz, it came programed when bough with an 9Mhz IF... anyhow made some tests with vfo on 17.5Mhz and my dip metter on 8.5Mhz (8421Mhz exactly)...there are some 79Khz diference I can't yet explain for my 9Mhz IF (17.5-9=8.5 != 8.421).
Almost for shure something is working in the radio since the audio is only when the osciltor is close to the wire conneced to the sbl-1 first mixer input, I am not so positive regarding the levels on the mixers... previous experiencies show'd me that big signals always are received, problem is the smal signals... I need to make an acurate power meter!!! Does anyone has a spare AD8307 that can send me? For a reasonable price of course :)


video

A photo of the building process.... the first mixer, the if preamp coil, pre-filter coil, relay for cristal filter switch and 9Mhz cristal filter.

No comments: