Hi Gary, Is the flange resistor mounted to a hybrid combiner square module or is the combiner on a pc board..? maybe even an interface or in-house made combiner on the amp or separate pc board?
s. >"Gary LaForce" <[EMAIL PROTECTED]> wrote: > > Working on an HMS amp an PA3-2GG-HMS amp right now that I replaced the > transistor on the A stage, and the flange resistor on the combiner, and c12 > mica cap on the A stage of the amp. All of this was causing only 80 watts > out of the amp and no current draw on the A stage of the amp. I put the amp > back in place on Tuesday and on Wednesdays I was pulling the amp back into > the shop due to a complete failure. This time the flange resistor on the > combiner had a blown again, both transistors were bad, and c12 bad arced on > the "A" stripe again. I tested swr at the site before and after the the > filters and at the antenna side of the polyphaser I see 5 watts with 110 > watts forward at the HMS PA I see no SWR or at least so little that I just > wiggles the meter needle. When I put the AMP back in-service I was seeing > current on both stripes of 15.3 amp + or - .2 amps and the supply voltage > was at 21.0 volts with 375watt out of the amp. > > > Any idea what is causing this problem I currently rebuilding this amp again > and don't what to blow it again. > > > > Gary > > > _____ > > From: [email protected] > [mailto:[EMAIL PROTECTED] On Behalf Of skipp025 > Sent: Friday, October 19, 2007 1:46 PM > To: [email protected] > Subject: [Repeater-Builder] Re: TPL amplifier - aka repeater operation at > the 250 watt power level > > > > > > Does anyone have any experience with the TPL 250 watt > > 2-meter amps for repeater use? > > Yep... > > > (bugs, reliability, operating manual/schematic availability). > > steve > > WA4BVO > > Bugs - none > Reliability - good > Operating Manual - Normally supplied with unit at the time of sale. > Schematic Availablity - Included within the manual although I have > a number of TPL Amplifier Manuals available for free download off > the www.radiowrench.com/sonic web page. > > A phone call to TPL with a valid credit card in hand always seems > to produce results if you must have the exact manual for your > specific amplifier. > > TPL-Amplifiers are about as generic as they come... repair is not > a big deal if you're used to working with modest - moderate power > rf stages. > > **** > > Sidebar: > > An increase to this relative higher power output level can be a > cautious road to travel. A circulator and/or trouble control > detection circuit is pretty much a must have. Little problems > normally not an issue at operation below the 60/80 watt power > level can quickly lead to an equipment melt down. There is very > little fudge factor and always no free lunch with 250 Watt > operation at/near 146 MHz. > > cheers, > s. >
