Hello my name is ***** ***** I have been servicing Hammond organs for over 40 years. As for your basic Question "is it worth fixing?" Before I can answer that you will have to decide what you are willing to spend, and what it is worth to you. For a basic answer, if you have to pay someone else to do it I would say no. If you are willing to repair it yourself, possibly. If you are blowing fuse after fuse there can be several causes. in the order of likely hood it would be 1) shorted rectifier diodes, parts cost about $5.00, 2) shorted output transistors, parts cost about $15.00, 3) shorted filter capacitor, parts cost about $20.00, 4) shorted power transformer. parts cost about $45.00.
I hope this has helped and if you have any additional problems, or would like any additional information or assistance, please do not hesitate to let me know. And if you can take a second to rate my service by clicking one of the stars at the top of the page, then submit, that would be greatly appreciated.
I wanted to check back with you to see if the problem was corrected. I am glad to help any way I can but without more information from you there is nothing I can do.