Off-camera flash / strobe pc sync cable hack mod

I finally bought myself a nikon sb-24 from ebay used. I have a nikon d90. I already purchased knock-off as-15 adapters because the nikon d90 does not have a pc sync port!
Now, you could buy the pc sync cable male to male. However, they are hard to find and pretty expensive. For example, just 1 foot is $10 not including shipping.

On the Strobist website, they tell you that you can buy a pc sync to household plug adapter. Then you only need to buy lamp cord in desired length and two female plug adapters, hook wires up. That was tedious to me plus electric cords are heavy.

Some other modders said you could use rca cable but you'd have to solder wires together and I didn't want to do that either.

Use a stereo audio cable to connect to pc sync cables.

You can and should buy a pc sync to 3.5mm plug (mono audio, 1/8"). For cheap. I bought two on ebay. $1.89 each including shipping. A bunch of people said not to use a stereo audio cable and to buy a mono cable. F that. Mono audio cables are rare and expensive. I bought an extension 3.5mm stereo audio cable, 25ft for $3.50 including shipping. The stereo cable works just fine. I've had no misfires.

However, there's one tiny problem. With your two pc sync cables to 3.5mm male plugs you need a 3.5mm female to female audio cable. They don't exist, or are very rare and with rarity comes expense.
So, what do you do? When you need to connect two male tips, you need a coupler. Those are female to female. Ebay has them for $1.

However, mine are in the mail. I wanted to use my flash now. I had an extra audio splitter, the type you'd use to plug into an mp3 player and allows you to plug in two headphones. I tested to see if I could use the two female sockets to send signal to each other. It worked! I put tape on the tip so I wouldn't cause any interference.

OR Use rca cables instead

Maybe you have a lot of rca cables lying around and want to use them instead of spending $3.50 for 25ft of 3.5mm audio cable. Ok. Here's what you need.
Buy the pc sync cable to 3.5mm audio. $1 Yes, buy 2. Next, buy these 3.5mm female to male rca adapters. I think you know the drill.

All kinds of these audio adapters are dirt cheap on ebay. Sure, shipping is going to take some time, it's Hong Kong. However, you won't be sorry.