When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
TPS4AC Improved New Parasitic Suppressor Assembly AL811H four 572/811 tubes:
$55.00
Instructions for installing parasitic suppressor is a new CTR Engineering TPS4 suppressor for AL811H amplifiers. It fits four-tube 811 and 572B amplifiers. I designed the original AL811 amplifiers and dozens of others.The original tuned suppressor was supposed to use 5-turns wound on a .375″ rod, spread to hole distances. There was also supposed to be a thick washer under the board to prevent shorting the 100pF resistor resonating capacitors near the choke. The resistor is a known internal inductance that resonates with the capacitors, it is not non-inductive.This suppressor was developed when non-inductive resistors were unavailable. This type of suppressor has superior performance to other more standard types..See this link for the operation of CTR Engineering TPS4 for 811H and TPS3 for AL811 are vastly improved layouts that reduce the chances of shorts from incorrect hardware. These boards provide more reliable parasitic suppression and are less critical for mounting.This system is vastly superior to hairpins and has a much better layout than the OEM Ameritron parasitic board. The TPS3/TPS4 system has a faster resistance slope with increasing frequency, and more suppressor series equivalent resistance at 811 problem frequencies that occur just below the FM broadcast band and around 225MHz.
