The least expensive way to get your C64 online is by building what I call a “Strikelink”, which is basically just a null modem that converts TTL signals to rs232 and vice versa. The parts listed below will allow you to hook your c64 to any usb port on a pc. Software on the PC side makes the “Strikelink” act as a virtual hayes modem at 2400 baud!
You’ll need a ch340g -> Serial/USB Device. You can find them on ebay for a few bucks. For 9600 baud, you’ll need to solder directly to the chip’s rts and cts lines, or find a ch340g -> usb with direct rts/cts out pins.
and this
Connect the TxD pin on the TTL Adapter to pins B and C on the User Port plug (RxD). Connect the RxD pin on the TTL adapter to pin M on the User Port plug (TxD). And connect the GND pin on the TTL adapter to pin N (Signal Ground) on the User Port plug. Install the driver, load up Leif Bloomquist’s BBS Server, and now you have a 2400 baud modem for $15 or less.
To add full 9600 baud capability
Add a wire from M to 5 on user port plug
Add a wire from B,C to 7 on user port plug
Attached a wire from L to 6 on the user port plug
Add the rts/cts lines to the ch340g from the user port (user port rts -> ch340g cts and user port cts -> ch340g rts)
Then use the UP9600 driver on Striketerm or CCGMS 2017
Use the instructions in the Connecting to C64 BBSes section on the left and look for the heading Using StrikeLink or other TTL/Serial Adapter/swiftlink/turbo232 (to use your PC as a virtual hayes modem)
Refer to http://www.hardwarebook.info/C64_RS232_User_Port for a diagram of the C64 User Port
Alwyz
1200baud 
Oh, the ebay link is dead.
do you have more information about the ebay hardware?
Yes, i think they relisted it. Any usb -> ttl 5 pin adapter will work, as long as it has rx, tx, and ground pins on the ttl side. This for instance is what you’re looking for. Tons of people make them .. http://compare.ebay.com/like/251117477526?var=lv<yp=AllFixedPriceItemTypes&var=sbar
if you have still a real com port on your pc you can make a c64 user rs232 out of http://www.ebay.com/itm/MAX232-RS232-to-TTL-Converter-Adapter-Module-Board-/390671091086?pt=LH_DefaultDomain_0&hash=item5af5cfc58e this kind of ttl adapter following the same wiring and use the pin 2 (5V) of the user port to power it
I’ve ordered all the parts to make a Strikelink that i want to use with my Vic. I currently use Striketerm with my Swiftlink on the 64 with tscser for the faster speeds. This method uses a nul modem cable from the swiftlink to the PC.
Is using the Strikelink method is it just VIC/Strikelink/USB to USB on the PC?
vic/strikelink/usb -> usb. then makesure the comports and bbs server are set up correctly on the pc
It looks like I will also need to find a male to male USB cable. A little harder to find.
Yes thats it, the device is just a ttl -> rs232 -> usb which acts as a serial port.
I was able to hack it into a userport reset switch and use an old USB cable. I use TCPSER and it works great. The one listed on eBay does not come with a driver but you can find it here.
http://www.instructables.com/id/Usb-to-SerialTTL-adapter/
Just and update on the Strikelink. It works on both the 64 and Vic-20. I have had problems with the data just stopping. On the 64 I can be downloading an entire disk without any problem and the next one it will just stop midway through. Same issue on the Vic-20 it will stop just reading a BBS e-mail. It may be a driver/setting issue that I have yet to figure out.
i’m not a hardware guru
So, i need a full working usb-device to use striketerm.
Please help me.
I may build a couple if there’s enough demand. Though the ez232 is only $30 from doppleganger, and I believe he has some in stock. That will allow you to connect at 9600 baud. Check the appendix of the Striketerm Documentation for his info.
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So I bult the upgraded version and no dice. I have verified all connections and while tcpser sees what I am typing the computer gets nothing back. Andy ideas?
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