Philadelphia's repeater activity started around 1963 with a repeater on 146.34/146.94 owned and operated by W3CKP. About the same time K3DSM put on a 146.94/52.525 repeater. Since these were personal repeaters they were available only when the owner was available or wanted them on.

There were hard feelings against a personal repeater since only one person had the say on how, when and what the operation was to be. As a result some 30 FM'ers met on November 1, 1967 at the WFIL studio's in Philadelphia to organize a club. The Main Line VHF Association, an inactive club, was chosen to simplify matters since it was still licensed and several of the old members were active FM'ers at the meeting.

A split-site repeater on .34/.94 was put on the air that night with the transmitter at K3DSM's home in Merion and with the receiver at K3JPB's home in Newtown Square. A 449 MHz link connected the two sites. W3CKP discontinued operations. Different locations were tested for coverage. The biggest problem was finding the best location to serve the most FM'ers. The area has numerous hills and the terrain didn't help matters no matter where a site would be located. Major site locations tested with fair results were Lankenau Hospital, Sellersville (old Western Union tower) and Berwyn Roller Rink. Berwyn proved to satisfy more people. Immediate preparations were made for a single site repeater at Berwyn. Receiver desensing was really bad.

In May of 1968, the Expo in Paramus NJ solved one of our biggest problems. We obtained a duplexer, a 4 cavity ring device, to allow one antenna to be used for transmitting and receiving without desense. Another problem was frequencies we were using. There were 10,000 reasons not to have a repeater on .76 and an equal number for not having it on .94. The club changed back and forth several times trying to please everyone which we finally found impossible. .94 was terrific coverage into Allentown some 55 miles away. Yet to the East there was a coverage problem 5 miles away.

Meanwhile another group, WA3IPP, put on a very good repeater in Sellersville on .28/.76. This repeater had very good coverage but was not solid near the city. It gave WA3BKO Berwyn lots of competition.

While the repeater was at Berwyn many improvements were made such as the addition of a mechanical wheel automatic ID, tape logging, hardline and a stationmaster antenna raised 40 feet above the rink. Control on 449 MHz with Secode had it's problems since the control receiver's IF was listening to Radio Moscow. The whistle-off feature had it's short-comings since testing disabled the system when anyone whistle-tested.

Simplexing on .34 among other anoying tactics finally called for a change of sites. Swarthmore was really poor. Coatesville covered Baltimore better than Philadelphia. Edgemont did not cover any better. The club wanted to go back to .76 but Sellersville was there now. It was decided to try to share the .76 frequency. WA3BKO was now in Penn Valley, central to the area to be covered. The duplexer could not operate on this pair of frequencies. The receiver was placed in North Philadelphia and linked on 449 MHz. Another receiver was placed in Devon also linked on the same 449 MHz frequency. Receiver selection was accomplished by hoping only one receiver heard the signal. Sellersville sent their .28 input to Penn Valley on another 449 MHz frequency. .34 and .28 could both access the .76 transmitter. At this point Sellersville transmitter was disabled. Power was raised, at Penn Valley, to equalize coverage.

On December 7, 1970 a vote was taken to merge the two clubs and form PARA.

Thanks to Gene K3DSM for the history of the Main Line VHF Association.

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