Put the mq4 file in the MT4 > Experts > Indicators folder, re-start MT4, go to one of the pairs you want to compare, click on View > Navigator, expand Custom Indicators, double click OverLayChart, fill in the SubSymbol of the other pair you want to compare (default is USDJPY), click ok and then wait for the next quote and it should appear (market has to be open) There might be a way to force it to appear without a quote coming in, if anyone knows.....
Once you added the indicator (that you can also add through Insert-->Indicators-->Custom) you drag the second pair from the Market Watch window on the left side. Once you see the two prices you can right-click on the added price and go to properties to change it. If you simply drag another quote from the Market Watch window it will change your underlying price, not the one you added.
Cabletrader, check this out http://en.wikipedia.org/wiki/Triangular_arbitrage In practice currencies are quoted with a bid ask spread, so a trader should be careful that he is actually buying at the quoted ask price, and selling at the quoted bid price. Other transaction costs, such as commissions often prevent the trade from being profitable.
Thanks, but I can't seem to get that to work I added the indicator to a Gbp/Usd chart, then I dragged Usd/Jpy across from Market Watch......and it changed the Gbp/Usd chart to Usd/Jpy, which is exactly what you said it would do. I must be missing something! Once the market opens then a price update will bring up the overlay pair, it's just I seem to remember there being a way to get it to appear without a price update coming in ie when the markets are closed or I'm offline.
Cheers for that, I don't think I'm fast enough or clever enough to exploit it, plus the way Oanda is with slippage and lagging quotes I think it would be difficult! Interesting idea though, I wonder how long you could get away with it before the broker got pissed
And also, I don't think oanda and other retail brokers allow us to buy at bid price or sell at offer price at all.
Try opening a fresh page: 1/ Window-->New Window-->EURUSD 2/ from the Navigator drag the OverLayChart custom indicator onto the page (USDJPY is fine), the second price immediately appears even if I'm doing all this offline. If you want to change EURUSD you drag-n-drop from Market Watch, and if you want to change USDJPY you right click on the USDJPY price-->OverLayChart properties-->Input tab-->change USDJPY there (make sure you use blocks). I've tested both ways (this and the one in my previous post) and both worked fine, you don't need a price update. As an interesting thingy, if your OverLay chart is set to e.g. USDJPY, and then you drag-n-drop USDJPY from Market Watch, the underlying EURUSD will disappear. If you drag EURUSD again, it will reappear. Good luck,
Thanks for the tips! I got it working in the end, turned out I needed to put an 'm' after the SubSymbol, ie USDJPYm