Sweno,
Thank you for your inquiry.
While Airmar Technology certainly manufacturers many common transducers that are utilized by various other electronics manufacturers, like Furuno, unfortunately the high & low frequencies are not always the same. In addition, the connector at the end of the cabling is not universal. For example the Furuno GP1971 uses a 10pin connector, while other manufacturers may use a connector which may be completely different.
The Furuno GP1871F & 1971F are capable out outputting either a single CHIRP band (high or medium or low....but not all three) OR they are capable of outputting up to 1kw at 50khz and 200khz.
Do you know the specific model number of your Airmar 1kw transducer?