I hope it will not repeat. They were replacing something in a substation that apparently went terribly wrong. Never seen such grid weirdness in a local blackout before. Various expensive appliances and air-cons died in the neighborhood. The power company will be receiving a long damage claims list.
I lived a mile away from Fermi Lab in Batavia, IL for 30 years, four TV's, one Threshold FET 9, one Krell 400i integrated, three computers and a SUN four gas analyzer all perished from the grid overload when they were playing with the particle accelerator. They would reimburse, but like any government entity it would take months.
I feel your pain.
The transistors missing from the kits are the 2SK170 and 2SK369BL.
The excuse, it has always been this way comes to mind.
So, I want to make the kits as limited in scope as possible so people with prior purchase or ownership of the rare 2SK do not have to re-purchase. I reuse mine by desoldering them out and placing them often in sockets.
The 2SK170BL amd 2SK369BL are getting rare, so one doesn't want to make the minikit $100+ just because 10 transistors make the majority of it.
Maybe in next GB I will make an all inclusive kit, or maybe drop the larger kits over time. Will have to see how demand is for this sort of thing. I also have the luxury of Tea-Bag junior having nowhere else to go or work to help out at this time.
My choice to make a larger kit this time around is because I suspect people are going to run into roadblocks looking for certain parts, as I noticed a lot of common parts I order are low or out of stock. The Covid crisis is quite real in this space. So I hunted down the parts for the larger kits. I have listened to all these parts and am quite pleased, as has my neighbor who built one. His friend who owns a Pass XP-25 loves it.
I hope this clears confusion on my mysterious ways of doing group buys.
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Tea-Bag, Thank you, but I have only doubt, for my ignorance (due to language, and evolution of project). I Know that this is a complicated DIY, so I am afraid of missing something of necessary and hard to find.
For example, I would have bought only a pair of 2SK369B. Now I know that if I change my cart, I can have level problem, so I chose to go with 2SK369BL quad.
All that you and Salas do is very apprecciated, I know that it require a lot of time and hard work, and I can only say thank you, thank you, thank you, for everything
30VA or 30V?
30-36V will work. The 36V burns off more voltage. So 5.6R R1 is more crucial. (Don't go down to 3.9R)
30VA, is that enough? I will let Salas answer that one.
For new from scratch Raw PSU builds I recommend 32VAC secondaries and RD/Link=1R. As already noted on the revised schematic. 30VA each is surely electrically enough. I usually recommend 50VA because most people opt for bigger when the 30VA and 50VA prices are close.
In case of already having two usual 15+15VAC transformers, left from other projects, their secondaries can be put in series for 30VAC per Tx. They are acceptable even if they result to 39V Raw DC minimum (when loaded with 100-150mA). Most mains are on the healthy side and most trafos output little higher when loaded with just few hundred mA and not nominally with few amps.
A cheaper option than using two 50VA Tx is use a single Tx of discrete 32+32V secondaries 50-100VA. That's also a standard off the shelf nominal spec. Its still a very decent solution, only the primary is common between channels.
For those who already have Raw supplies ready from the previous, they are workable. 40-45V Raw DC is nice for the new shunt reg section's input. Max safe feed to this reg is 50V. It will pull in 100mA with R1=5.6R as noted on its schematic. That's almost the same loading as from the older FSP shunt.
So your older tests with your 36VAC transformers on your own mains for acceptable RawDC via RD/Link value tuning when using 470R dummy loads are still valid. If they need some further Raw DC output trim down, increase RD/Link.
In case of already having two usual 15+15VAC transformers, left from other projects, their secondaries can be put in series for 30VAC per Tx. They are acceptable even if they result to 39V Raw DC minimum (when loaded with 100-150mA). Most mains are on the healthy side and most trafos output little higher when loaded with just few hundred mA and not nominally with few amps.
A cheaper option than using two 50VA Tx is use a single Tx of discrete 32+32V secondaries 50-100VA. That's also a standard off the shelf nominal spec. Its still a very decent solution, only the primary is common between channels.
For those who already have Raw supplies ready from the previous, they are workable. 40-45V Raw DC is nice for the new shunt reg section's input. Max safe feed to this reg is 50V. It will pull in 100mA with R1=5.6R as noted on its schematic. That's almost the same loading as from the older FSP shunt.
So your older tests with your 36VAC transformers on your own mains for acceptable RawDC via RD/Link value tuning when using 470R dummy loads are still valid. If they need some further Raw DC output trim down, increase RD/Link.
Each M1 will dissipate 1W and each M2 2.4W. When for 32VAC Tx and 100mA CCS current setting in the shunt regs (R1=5.6R). Totals 6.8W four Mosfets dissipation. Not little. In this version I recommend case sinking with isolation pads and nylon grommets. Hence the cut outs on the 1.3S sections. To aid M1 M2 underneath board's edge mounting style having their tabs backs against a panel surface.
In an effort to avoid small internal radiators more intensely warming the air in the box. Because the input stage when in MC mode is peculiar with temperature swings. A metal case spreads the heat better on its big surface which is also in contact with the room's air.
Hi Tea
I sent you a PM. I have been trying to access the GB spread sheet to order with no luck.
I listed what I want in the PM and the total.
I found your Paypal info from when you did the matched Harris transistor GB.
Edit: I sent payment with a note listing what I want to order. Please confirm receipt via PM.
I sent you a PM. I have been trying to access the GB spread sheet to order with no luck.
I listed what I want in the PM and the total.
I found your Paypal info from when you did the matched Harris transistor GB.
Edit: I sent payment with a note listing what I want to order. Please confirm receipt via PM.
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Mouser Parts list
Yes i did. I made up two list. First list is for all Phono board parts needed, if you already have the minikit parts and semiconductors. Mouser project ID is 7696b551f4 for this list. Some parts are almost out of stock so you will have to search for proper replacement.
Second list covers all parts needed for the RAW PSU board. Mouser project ID is f1a43ee303
. As you can see by the price it makes sense to buy the kit directly from tea bag.
Remember Mouser will add your local VAT at the end of the checkout process.
Yes i did. I made up two list. First list is for all Phono board parts needed, if you already have the minikit parts and semiconductors. Mouser project ID is 7696b551f4 for this list. Some parts are almost out of stock so you will have to search for proper replacement.
Second list covers all parts needed for the RAW PSU board. Mouser project ID is f1a43ee303
. As you can see by the price it makes sense to buy the kit directly from tea bag.
Remember Mouser will add your local VAT at the end of the checkout process.
Thanks AddiDub. I tried to look for both project IDs but can't seem to find them. Its weird.
The only reason for me wanting to order from Mouser is because I will need to buy the big caps as Teabag doesn't supply those and Mouser has minimum order quantity to qualify for free shipping. Bummer.
The only reason for me wanting to order from Mouser is because I will need to buy the big caps as Teabag doesn't supply those and Mouser has minimum order quantity to qualify for free shipping. Bummer.