|Planetary Radio Astronomy
Radio Jove Electronics Tips
1. Soldering the Radio JOVE Receiver Kit
2. Using a VCR as a recording device
| 1. Soldering the Radio JOVE Receiver Kit
A quick tip on soldering. Use only the recommended soldering iron (25-30 watts), preferably temperature regulated with a small tip. Keep a wet sponge near the soldering iron. KEEP YOUR SOLDERING IRON TIP CLEAN! When it gets dirty (black crud on tip), wipe the tip on the sponge. When you solder, place the iron-tip in contact with the wire /component AND in contact with the printed circuit board (contact both at once). Another tip: to get the solder to start flowing after cleaning the tip, quickly melt a drop or two of solder onto the tip (called "tinning the tip") and then immediately apply the tip to the board/wire, heat both up and apply solder to the joint. When solder flows smoothly and covers the joint remove the iron. The solder joint should be shiny, not gray and dull (a cold solder joint). This process should not take more than 5 seconds from grabbing the iron to putting it back in the holder. If you apply too much heat to the joint, the heat may damage a component. You might practice soldering on an old PC board (preferably with holes in it). Try soldering scrap pieces of resistor leads to a terminal on the board until the connections look good. That way you can get a feel for how much heat is needed to get a good solder flow in a minimum period of time.
Repeating the soldering procedure:
Wes Greenman UF-Astronomy
| 2. Using a VCR as a recording device
I have tested an inexpensive ($70-$90) VCR (must have A/V inputs and outputs) and the results are very good. On the Extended (6-8 hours depending on tape) speed the audio response was about 35 kHz. Since the Jove receiver's response is about 6 kHz the VCR is more than adequate. There was some question whether or not you also need a video input to provide sync for the audio channel. My tests indicate that you do not need a video input however it was suggested that if you have an inexpensive video camera (cost about $80) you can use the video camera to photograph an analog clock. Then when you fast forward or reverse you can quickly go to a specified time (assuming you have kept a good log). From the jovelist emails I know that other's have already had success using the VCR as an audio recorder so I know it is a practical solution to long term recording.
In my tests, the VCR apparently had no limiting (ALC, etc.) since the dynamic range was a huge 60 dB (we only need about 20-30 dB). Also, since VCR's are all stereo, you can use one audio input to the VCR from the Jove receiver and the other audio input to the VCR for WWV time, assuming you have a short-wave receiver. In this case, you don't need the Video Camera to photograph a clock.
Wes Greenman UF-Astronomy