Gilfer Associates in Park Ridge, NJ published the books until Ferrell's death prior to 1997. It's also worth noting that via Gilfer Ferrell also published other books, Guide to RTTY frequencies, collection of Radioteletype Frequencies. Ferrell was also the CEO of Gilfer associates. It seems impossible that he'd deliberately launch one series of Confidential Frequency lists then another co-branded with his surname. I assume for that reason that Grove edited the first two editions, then Ferrell took over and eventually put his name on the tin.
The book featured a very short introduction and a bit of information on the mechanics of shortwave radio and gear. The rest of the book for hundreds of pages was just a frequency directory by frequency, focused on HF activity between about 4 KHz and 28 KHz. More here. Below is a list of what I believe to be the correct years for the various editions and authors.
- First Edition -1972 - Gilfer Associates by Robert B. Grove
- Second Edition - 1976 - Gilfer Associates by Robert B. Grove
- Third Edition - 1979 - Gilfer Associates by Oliver P. Ferrell
- Fourth Edition - 1980 - Gilfer Associates by Oliver P. Ferrell
- Fifth Edition - 1982 - Gilfer Associates by Oliver P. Ferrell
- Sixth Edition - 1986 - Gilfer Associates by Oliver P. Ferrell
- Seventh Edition -1988 - Gilfer Associates by Oliver P. Ferrell
- Eighth Edition - 1992 - Gilfer Associates by Oliver P. Ferrell
- Ninth Edition - 1994 - Gilfer Associates by Oliver P. Ferrell
- Tenth Edition - 1997 - PW Publishing by Geoff Halligey
- Eleventh Edition - 1999 - PW Publishing by Geoff Halligey
- Twelfth Edition - 2001 - PW Publishing by Kevin Nice
- Thirteenth Edition - 2003 - PW Publishing by Kevin Nice
In the UK, Bill Laver printed at least eight editions of his own Short Wave Listener's Confidential Frequency List. This complimented his other directories of Marine, VHF/UHF, and RTTY frequencies. Laver threw in the towel in 1994. By all reports the Ferrell's own series ended in 2003. There is no comparable modern publication, even the Klingenfuss Guide to Utility Stations has been out of print for a few years. [SOURCE] In some ways this has been supplemented by lists and boards online, but the lack of a canonical source limits their utility. The Farrell's books remain interesting historically, and some of these old stations still operate. Copies of most editions can get picked up used on eBay for just a couple bucks.