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    SP14 - Tips and Tricks requested

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    Zimmer64

    Posts: 98
    Join date: 2013-01-29
    Age: 50
    Location: Switzerland

    SP14 - Tips and Tricks requested

    Post by Zimmer64 on Fri May 03, 2013 10:48 am

    Hello fellow tube lovers,

    I am about to start putting an SP14 kit together. Are there any tips and tricks that you are willing to share? Any pitfalls? I am more or less a newbie in the field and do not have any engineering background either. I am learning as I go along and depend on help from the community.

    Thanks a lot for any input.

    Michael

    Ps: I will document my build and post here

    tubes4hifi
    Admin

    Posts: 964
    Join date: 2008-11-30

    Re: SP14 - Tips and Tricks requested

    Post by tubes4hifi on Fri May 03, 2013 1:53 pm

    check out the two or three links to builds on my website at www.tubes4hifi.com/SP14.htm


    Last edited by tubes4hifi on Fri May 03, 2013 7:57 pm; edited 1 time in total

    DarthBubba

    Posts: 75
    Join date: 2012-05-05

    Re: SP14 - Tips and Tricks requested

    Post by DarthBubba on Fri May 03, 2013 7:16 pm

    tubes4hifi wrote:check out the two or three links to builds on my website at www.tubes4hifi.com/SP14.htm

    www.tubes4hifi.com/SP14.htm


    Zimmer64

    Posts: 98
    Join date: 2013-01-29
    Age: 50
    Location: Switzerland

    Re: SP14 - Tips and Tricks requested

    Post by Zimmer64 on Sat May 04, 2013 2:45 pm

    Thank you guys. I have looked at the link earlier, of course Very Happy I was more looking for mistakes or obstacles that other have made or come across and a tip how to avoid those.

    Michael

    TorontoDave

    Posts: 23
    Join date: 2013-03-18

    Re: SP14 - Tips and Tricks requested

    Post by TorontoDave on Tue May 07, 2013 11:22 am

    Zimmer64 wrote:Thank you guys. I have looked at the link earlier, of course Very Happy I was more looking for mistakes or obstacles that other have made or come across and a tip how to avoid those.

    Michael

    I just put mine together last night. Some possible pitfalls.

    1) When soldering components - solder from the bottom and check from the top to ensure the join is correct/solid.
    2) When soldering diodes verify the direction of the diode. The side with the band should match the the box on the board schematic.
    3) When soldering the electrolytic capacitors the long wire is positive and goes in the square hole (be sure it matches the + lead on the schematic.
    4) Presort your resistors so they match based on labels and color bands.
    5) Identify the resistors based on labels and solder them first (easiest to identify)
    6) Identify the resistors based on bands next - several are easily identifiable (like 330, or 470)....once identified solder to the board - work backwards (if its known solder it). It helps identify the parts.
    7) periodically check your work against the photo's Roy posted above.

    Once the board is soldered you can start work on the wiring and jacks - this is the stage I'm at now (just waiting for some parts in the mail).

    For resistors I use http://www.elexp.com/t_resist.htm to identify the color codes.

    David

    tubes4hifi
    Admin

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    Re: SP14 - Tips and Tricks requested

    Post by tubes4hifi on Tue May 07, 2013 3:35 pm

    don't relay on color codes, just sort the resistors by colors, and then DOUBLE CHECK THEM with a meter !!!!

    Zimmer64

    Posts: 98
    Join date: 2013-01-29
    Age: 50
    Location: Switzerland

    Re: SP14 - Tips and Tricks requested

    Post by Zimmer64 on Wed May 08, 2013 2:46 pm

    Thanks guys. I started the build today. I checked all resitors with my meter and put them onto the board following the schematics, but did not solder yet. I will double check tomorow before I solder.

    One question tough. Compareing to the pics on Roy's website, there seems to be a difference. I dont see the 100 Ohm resistors R11 - R12 on the pictures. Have I made a mistake or is mine a different version of the board?

    Best

    Michael

    tubes4hifi
    Admin

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    Re: SP14 - Tips and Tricks requested

    Post by tubes4hifi on Wed May 08, 2013 3:41 pm

    Michael, the pics on the website are an older version, R11 and R12 are there, closer to the rectifier tube

    Zimmer64

    Posts: 98
    Join date: 2013-01-29
    Age: 50
    Location: Switzerland

    Re: SP14 - Tips and Tricks requested

    Post by Zimmer64 on Thu May 09, 2013 12:22 pm

    Thanks guys. I started the build and made good progress. The board is mostly a mirror image for each channel. Except two resistors! I almost fell for it. Be carefull where R20 and 21 goes. Those two buggers change the sort order Shocked

    I double checked and measured every component before I soldered (I hate to de-solder......).

    Best

    Michael




    TorontoDave

    Posts: 23
    Join date: 2013-03-18

    Re: SP14 - Tips and Tricks requested

    Post by TorontoDave on Thu May 09, 2013 1:41 pm

    Hey Michael - looks just like mine (except for the Cap upgrade).

    David

    ruffian

    Posts: 43
    Join date: 2010-02-26

    Re: SP14 - Tips and Tricks requested

    Post by ruffian on Thu May 09, 2013 10:03 pm

    Looks like you are well on your way there. The power supply area is not a mirror image as I recall.

    Looking forward to seeing it come together.




    TorontoDave

    Posts: 23
    Join date: 2013-03-18

    Relay Board

    Post by TorontoDave on Fri May 10, 2013 12:04 pm

    The schematic/documentation doesn't seem to cover the relay board.

    Based on what I can see in the sample builds I think it is as follows:

    1) High voltage +- to the relay board (230/240V) - High voltage from transformer. If you got a discrete 115/230V high voltage transformer remember that it needs to be wired in SERIES to get the right voltage.
    2) L/R Out goes to input on board
    3) S1-S5 goes to pins 1-5 on the selector switch
    4) S0 goes to pin A on the selector switch
    5) Ground to common Ground

    Not really sure how to wire tape switch if you are using the relay.

    David

    Zimmer64

    Posts: 98
    Join date: 2013-01-29
    Age: 50
    Location: Switzerland

    Re: SP14 - Tips and Tricks requested

    Post by Zimmer64 on Fri May 10, 2013 12:16 pm

    Thanks Dave. I do not use a tape switch, but I actually struggle a bit with the relay board. I dont think the input selector relays work with high voltage. I also struggle a bit with the toroids. Question is where to solder the secondaries to.The schematics are showing different toroids. I have 3 toroids with secondarie 2x115, 2x18 and 2x6 volt. I am aware, that I have to wire the primaries of the toroids in series for 240 volt operation. I also did not figure out where to wire the LED. I have sent a couple of questions to Roy re this and await his reply. I will keep you posted.

    Michael

    Zimmer64

    Posts: 98
    Join date: 2013-01-29
    Age: 50
    Location: Switzerland

    Re: SP14 - Tips and Tricks requested

    Post by Zimmer64 on Fri May 10, 2013 12:41 pm

    Roy just replied. Here is an updated schematic:


      Current date/time is Sat Jul 26, 2014 12:04 am