Great pleasure this morning to receive the first batch of the gyrator PCB. After extensive testing we refined the layout and options for the PCB and now we have the final product ready for shipping! Unfortunately I will not be able to do some testing and shipping before end of February and I received a large number of requests already. I’m sure this batch will fly very quickly so please confirm your requests.
I will post soon the specifications and some circuit examples for this flexible gyrator board which can be used for DHT preamps (e.g. 4P1L, 01a, 26), amplifier drivers, A2 drivers, LTP drivers, parafeed output stages and more!
So check the For Sale section soon for more information.
Some days ago we discussed in DIYAudio using this board for a 2J27L preamp like this one:
The output FET follower is needed to for valves which have low current and high anode resistance which will struggle to drive large capacitances. The FET follower of your choice can be used instead.
A minimal circuit which sounds fantastic is the basic configuration of this PCB. With few changes this circuit can be used on many DHTs like 26, 4P1L, 10Y, 30, 30sp, 12, 71a, 45, 46, etc:
If you want to send me your requests please use ONLY the form below:
Boards tested and abused over the weekend. They work like a charm with 2SK170 FET. If SMD BF862 is used instead, an extra 15V zener is needed for protection between drain and source to protect them from any surge at power on (or power glitch).
The BF862 is an amazing fellow!
Boards are of superb quality: 2oz (70um) copper with ENIG finish on a 1.6mm FR4 laminate.
cheers
Ale
Hi Ale,
last time I heard you, before sending me the boards, you spoke about building instructions, BOM and circuit examples to be released.
At the time being this kind of info is still missing on your blog.
When do you expect to release them?
Hi Michele
Just ping me an email and will send you all the info
Thanks!
Ale
Hi Ale… Received 4 units gyrato PCB in March, came with BOM but no schematic!?
Why is R6 , 4.7M not on the list!? Why there’s two C1, 100nF and 220nF?
Planning to loaded my EL3N @ 14mA with it.
Thanks A Lot.
Best Regards from Singapore.
Desmond Kwan
Hi,
I will resend build guide with all the details and the answers to your questions above.
Thanks
Ale