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Precision Power Scale Circuit
#5
Hi Guys

One of the advantages of cord-wood construction is a reduction in PCB size, which allows kits like SV1 and SV2 to fit into tinier spaces inside an amp chassis. The disadvantage of cord-wood construction is increased build time.

For example, the SV1-D has a about half of its components lying flat and the rest as cord-wood. All the flat resistors can be installed in one go and then soldered, where each cord-wood mounted resistor has to be inserted and soldered as a step unto itself. The assembly time for the SV1-D is about one hour. It is similar for the SV1-M36, which has a few more parts. SV2-D and SV2-M36 take a bit less time, maybe 45-minutes or so.

The Precision Power Scale SV1-Zh and SV1-Zp take two hours to assemble as there are very few lay-down resistors.

It is a deceptively larger increase in assembly time for the SV2-Zh or SV2-Zp compared to the SV2-D. This is another two hour build BUT once you are done you have both the SV2 and VCK circuits built AND the precision of the Z circuitry. The Zh and Zp represent a complete Power Scale solution for cathode-biased amplifiers and take less board space than the previous combination of kits required.
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Messages In This Thread
Precision Power Scale Circuit - by K O'Connor - 12-11-2025, 01:53 PM
RE: Precision Power Scale Circuit - by K O'Connor - 01-23-2026, 01:39 PM
RE: Precision Power Scale Circuit - by K O'Connor - 01-23-2026, 02:21 PM
RE: Precision Power Scale Circuit - by K O'Connor - 02-25-2026, 01:38 PM
RE: Precision Power Scale Circuit - by K O'Connor - 02-28-2026, 02:57 PM
RE: Precision Power Scale Circuit - by K O'Connor - 03-04-2026, 08:08 PM
RE: Precision Power Scale Circuit - by K O'Connor - 04-15-2026, 10:09 PM

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