By the time the 486 came out, diskettes were 1.44MB. You're trying to copy files larger than that? Most software for that computer came on diskettes in the first place.
But the simple way is to get a null-modem-USB cable (https://www.amazon.com/USB-Serial-Adapter-Modem-9-pin/dp/B008634VJY/ref=sr_1_4). Hook one end to your vintage PC the other to your modern PC.
Programs like Kermit should still be available for both PCs (and will fit on one floppy so you can get it to your vintage computer) and do a wonderful job of transferring multiple files. You may have to experiment a bit to get the max baud rate that will work with the older computer, but it should be pretty high so the files will transfer pretty quick.
5 months later... I just bought a Russound Cav 6.6 and found that HA integration. You went wifi, but I assume I could just use this cable since my HA server is in the same rack that the CAV 6.6 is going into, right?
Ok, so I found the order receipt, and i'll try to remember what all i bought to support the build.
Parts
Those first 4 were all from the pcengines site (it looks shady/old as hell, but they're legit)
Other things
Guide
As for any guides, like i said i can't seem to find the one i used before, but I did find this one, and it does mention that things changed for the installation steps after pfSense 2.4, hope it helps.
This one works with my older PowerConnect switches and Putty:
https://www.amazon.com/StarTech-com-Modem-Serial-Adapter-ICUSB232FTN/dp/B008634VJY
The first cable is a cisco cable the second is wrong also. This is a null modem to usb
I bought this USB->null modem cable. Worked like a charm.
Startech USB serial cable, that uses the supported chipset by the Windows IoT drivers, connected to the PowerView hub's RS232 cable. There is a male-to-male connector in between.
http://www.amazon.com/StarTech-com-Modem-Serial-Adapter-ICUSB232FTN/dp/B008634VJY
http://www.amazon.com/Your-Cable-Store-DB9-Adapter/dp/B002CX661K
Once connected, running devcon via PowerShell shows good status:
devcon status usb*
USB\VID_0403&PID_6001\A103M71C Name: USB Serial Converter Driver is running.
The first one you linked will allow you to access a serial connection over an Ethernet network. If that's what you want then great but it's probably not what you want to allow you to take a laptop to a network switch and manage it.
The second item you link to is just a port converter. It converts from a DB9 connector to an RJ45 connector.
What you need is something more like this. This will provide your laptop with an actual serial port. You will then need the appropriate port converter to connect this to the network switch. Most switch manufacturers use the same RJ45 serial pin-outs that Cisco uses so something like this will do the trick. It's usually known as a "Cisco console cable". Some manufacturers do their own thing so you'll need an appropriate console cable to match their own pin-out.
Once you've got the physical stuff sorted out you then need to find out which serial port your USB to serial adaptor is showing as. This can vary from PC to PC and even from USB port to USB port. Plug it in, open up Windows "Devices and Printers" and it should show up with the relevant COM port number, eg COM4.
Once you've got that you then need to find out the serial port speed and settings that the network switch will expect. It's usually something like 9600 bits per second, 8 data bits, no parity and 1 stop bit (often written as "9600 8n1"). You'll need to set up putty to match this. You should then be able to successfully use the switch's console port.
Back in the day, I connected a null-modem RS-232 serial cable between my PC and C64 to transfer files using terminal emulators. (Note that the C64 doesn't have a standard RS-232 port - you need to have an adapter on the user port to convert the voltage).
You could get a null-modem USB serial cable for your PC, and then hook it up to a RS-232 connection on your C64.
EDIT: A quick search online found the SD2IEC SD Card reader for the C64 - it definitely looks like the right way to go.
I'm using this USB to RS232 Null Modem cable: http://www.amazon.com/StarTech-com-Modem-Serial-Adapter-ICUSB232FTN/dp/B008634VJY/
It has an integrated FTDI USB UART chip.