First, you don't need the VidMod to read the flash (TSOP) on any 301-013.
To even know if you need a VidMod you will have to remove the receiver cover and determine if you have a single TSOP, or dual TSOPs. If you have a single, the U10 location will not have a flash chip. In that case you would need a VidMod to be able to write (flash) the TSOP when you need to repair it after an ECM. (unless you use a hardware TSOP lock or softlock).
To read more about 301-013's and the issues with getting a reading via a Jtag, search or browse the forum, and also look at the info at bellexpress.vu (Milis site).
In addition, you should look at the VidMod article, especially the end of it, as it shows something you may need (a jumper) to be able to successfully read that 301-013.
Also, I have seen where you sometimes can't get a good read with an extension cable attached. Try to hook your Jtag DB25 connection directly to your parallel printer port instead of using the extension cable. It may take a bit of doing, but it has worked for some.
Also, make sure Jkeys is set to use the correct printer port if that is what you are plugged into, not the jInterface (unless you have a jInterface of course). Check the Device Manager in Windows to see what the resources are for your printer port. They will likely be 0x378, 0x278 or 0x3BC, then set the preferences in Jkeys accordingly.
Good Luck!
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