Quote:
Originally Posted by John Folsom
It has been my experience that the 630/621 chassis do not have very good high frequency response. I was unable to get 3.58 mhz through my 630. Anyone else have similar results?
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Since the 630TS that I scored on eBay years ago is still in the process of undergoing Restoration as a series of successive stages of work (another case of an eBay seller's failure to follow very specific instructions and total disregard for Insurance TOS specifications having resulted in severe "Brown Rot" and no Insurance coverage for the cost of replacing the damaged parts), the many "630-type" I've restored on which I have obtained textbook-optimal response curves and test-pattern displays have all been "630 Clone" models and some 8TS30's built after implementation of at least some of the subtle Production Changes which weren't included in the original RCA production models of the 630TS. I've found that the clone sets as far back as the Fada 799 have all produced textbook curves and only slight loss of sharpness above 3.58 MHz on display of the test pattern. When using the B/W output of one DVD player having both Composite and Component video outputs, there is considerably less degradation in Resolution and Response than expected near the 325-Lines / 4.0 MHz extreme. The 8TS30's I've serviced have produced test pattern displays very near the Ideal display parameters, showing very little difference when the onscreen image is compared side-by-side to a high-quality printed Test Card (master image from PC printed on matte Photo paper using a $300-List-Price printer with one of the best Photo print capability specifications of any "Home Office" type printer). The 721's IF response isn't easy to get "just right" on versions not equipped with a 27.25 MHz trap, but it can be done. My first time aligning a 721TS took several hours to complete, although much of that was because I was still using a very "Rube Goldberg" arrangement of test gear (Precision E-400, Precision E-200C, Heathkit IM-4110, and Tektronix 547 'scope), injecting Sweep and Markers separately, and setting Marker points with the E-200C dial while watching the IM-4110 readout for each step of alignment. Here is a screenshot of "Law & Order" showing over-the-air reception on that first 721TS that I aligned, taken in 2002.