DYNACO ST-70 6GH8 6GH8A Stuffed Driver board + NOS Telefunken ECF82 Matched pair

This is Dynaco ST-70 driver board PC-3. It’s developed and designed to be drop in replacement and it follows original wire hole layout, but it’s modified to use widely available 6GH8 / 6GH8A / 6KD8 / ECF82 tubes instead of obsolete and hard to find 7199 tubes.  You can find many quality NOS tubes of any of these types for normal prices and you can enjoy tube rolling with this driver board.  It’s also modified to accept modern and NOS coupling capacitors of various types and dimensions.

It’s made of hi quality epoxy fiberglass FR4 material 1.6mm (0.062’) thickness, it’s double sided with solder rings on top layer.  Solder reflow process is done on both layers and also inside every hole and blue solder mask is applied on both sides. All connections and elements on the board are silkscreened with original DYNACO numbering, so you can use original DYNACO ST-70 manual to complete it.

This is complete board! One brand new PCB, ceramic sockets, Hi quality MKP coupling capacitors, silver mica capacitors, metal film, metal oxide and carbon oxide resistors and one NOS matched pair (two tubes) of 6GH8A ECF82 Telefunken made back in 70s. Every pair is selected from the same batch with same date codes and tubes are real platinum matched pairs, tested on calibrated METRIX U61-B tester.

All coupling capacitors are high quality Hi Quality MKP Metallized Polypropylene (PP) Capacitors. 120nF are used vs original 100nF, for a bit better bass response. Also silver mica capacitors are used, metal film, metal oxide and carbon resistors for good performance and lowest hum.