It is more than possible you have a crystal cut on the wrong mode. It's not hard to order replacement crystals although you run into the min order or higher costs depending on where the new rocks are ordered.
You might order and try both the oven and non-oven operation. I run a TA51 6 Meter Exciter without the OV-1 oven, which on low band is not that big of a problem. Crystal controlled (non-synth) equipment is being pushed aside by current technology. If you want a practical alternative... buy a Midland XTR Low band Mobile off EBay, reprogram it onto the six meter band, retouch/adjust the vco, receiver front end & tx sections for the higher range and you're off and running. I've got "a few" Syntech and XTR Mobiles already on six... and they make great repeaters. Not to mention there is a yahoo group for Midland Radios. cheers, skipp > Joe <[EMAIL PROTECTED]> wrote: > > I'm thinking that I might just have a bad crystal, but have no way to > prove it. The crystal does have the Hamtronics crystal oven on it, but > I don't think that should be the problem. > > My opinion right now is that the TA51 6 meter version is just not a good > design and probably should be pulled from the Hamtronics products. The > specifications on the website state that the transmitter can do +-5Khz > of deviation, but the instructions say that it cannot. The 6 meter > repeater that they now sell uses a different synthesized transmitter. > > 73, Joe, K1ike > > > Kevin Custer wrote: > > > > Joe wrote: > > > >> The distortion is acceptable at 2.5Khz deviation, but not at 3Khz. I > >> have had the 144Mhz and 220Mhz versions of this board and never had this > >> problem. > > > > As you said earlier Joe, it's the multiplication factor that is > > killing you, with this type of phase modulator. > > > > I have never tried my FM modification on a 6M TA-51. I do however use > > it on UHF where the FM modulator replaces the phase modulator > > totally. I know I advertise that my FM mod is only for PL generation > > , but if driven from a good clipper/filter, like the AP-50, you can > > use it on the entire voice/pl range. > > > > It may be difficult to FM a crystal far enough to get 5K of totally > > undistorted audio from a Hamtronics 6M TA-51, but I'd try it..... Use > > a good varactor. > > > > http://www.repeater-builder.com/hamtronics/ta-51pl_mod.html > > http://www.repeater-builder.com/products/ap-50.html > > > > Kevin > > >
