Here are the USB to RS232 units I own and use at least weekly.
http://www.serialio.com/products/adaptors/usb_serial.php
http://www.amazon.com/Belkin-SERIAL-PORT-ADAPTER-F5U409-CU/dp/B00009L7MI/ref=pd_lpo_k2_dp_k2a_1_txt?pf_rd_p=304485601&pf_rd_s=lpo-top-stripe-2&pf_rd_t=201&pf_rd_i=B000067RM7&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0C6410BXRVTMH8QNMXXK
I also have a Cables To Go unit but suggest you look at the Keyspan unit like this one -> http://www.walmart.com/catalog/product.do?product_id=5934005
I have a JVC GR-SXM920U camcorder that has a 2.5mm plug to serial for downloading pictures (built in memory no card)- problem is my computer does not have a serial port only USB ports.
How do I connect the serial to usb?
Is there a 2.5mm 3 contact plug to USB cord I can use?

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