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Hi,
Wonder if anyone can help. Q1. Fresh off of eBay, this SA is having terrible problems with input RF leaking straight through to the IF on the lowest RF range. I assume that the input mixer is shot (441-0671-03). If I remove the LO feed to this mixer, the expected signal goes away, but the crud remains. I assume that the IF on the lowest RF range is close to one of the broadcast bands (TV or FM). The mixer assy has two diodes which look like they should be easy to replace. Does anyone have a schematic for this assy or maybe just tell me what these devices are and some idea where I might get replacements. Q2. I feed in 144 Mhz and crank the SA centre frequency lower (130MHz) and the trace shifts left (I rather expected it to shift right). I assume that this could be connected with the busted mixer ? Q3. This one is definatly operator error. The mid range 'B' has two scales 270 - 900 and 800 - 2000MHz. How do I switch between these two ranges (!) Thanks in advance. Mark. |
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