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Spider27

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About Spider27

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  1. Thank you.. Yes, those TK caps seem replacement of originals. Grey ones are Unicon caps. Since those capacitance values are still strong, not sure if I should recap those yet. I would like to find out what caused shorting 2 sets of BJ transistors at TR511 and TR509 then recap if I can fix the issue first. What is confusing about schematics is some of them does not show unit of measurement. For instance R541 shows 0.5 (2). My guess is that it means 0.5ohm at 2w but not 100% sure if it is the other way around. 😅
  2. Have gone through checking all of 47 caps with capacitance meter and @mbz is right. Someone has worked on this and replaced caps already because all of caps seem fairly new and capacitance value is still strong. There are a couple of odd things noticed. 1) C257 capacitor is meant to be 16V 4.7uf but 10V 10uf cap is installed so it is out of spec. Lower voltage value is not good if I understood correctly so will replace this to correct value. 2) The schematic says 0.5 (2) for all 4 (R541, R543, R542, R544) resistors. I guess that it means 0.5ohm 2W. However, R541 & R543 have 2W 5% 0.47ohm resistors and R542 and R544 have 2W 5% 0.51 ohm so both channel has slightly different value. Not sure if it is important but will replace blackened 0.47ohm resistors to 0.51ohm resistors to match with the other channel.
  3. Item: Digital Oscilloscope Price Range: TBC Item Condition: Used Extra Info: Looking for a digital oscilloscope to learn and play with. I guess that Siglent SDS-1052 or equivalent would be good for beginners. Nothing fancy or expensive one is required but good enough so no need to upgrade soon would be sufficient. If you have too many or have one just sitting idle and shoot me a PM.. Thank you...
  4. Very interesting design. Does this need to be lifted up 90 degrees each time record is to be changed? And, possible to know the mounting distance?
  5. Due to lockdown, pick up might not be possible. Price included shipping any metro regions in Australia.
  6. Gorgeous looking TT in red. GLWS. (P.S.) May I ask what timber the cabinet is made of? It also look stunning!!
  7. Further information: Superb tube phono preamp with separate power supply. Built extremely well and look gorgeous with solid timber planks on top. Only reason that I am selling is because I recently bitten by DIY bug and decide to want to give a go with DIY route hence selling. Condition is excellent and I cannot see any mark or dent on the unit. [BONUS] Brand new custom power cable (1.5m length) which is so much better than stock kettle cable is included. Shipping is included to most of metro regions. It will be packed well for safe delivery. Here is product link to find out more details. https://www.osbornloudspeakers.com.au/r-40 Direct: $1,295 Flagship. All valve to MM and high quality transformer to increase gain to MC. Every person who has ever tried this unit, has bought one. It has a stunning open and natural sound that makes it our biggest seller and it is always chosen over much more expensive units. Seperate power supply for a low noise floor. CONTROL FUNCTIONS: Power On/Off , Switch MM / MC and Switch High / Low HARMONIC DISTORTION: (for 2V RMS at output): 0.01% INPUT IMPEDANCE: 47(MM),5 /40 ohms(MC) INPUT INTERFACES: 1 group (RCA) OUTPUT INTERFACES: 1 group (RCA) GROUNDING INTERFACES: 1 group SIGNAL/NOISE: 80dB(mm),70dB(mc) CONSUMPTION: 10watt VACUUM TUBE: 12AX7 x 2, EZ80 x1 Photos:
  8. Thank you.... Understood . I will order together with other caps and will give them a go. Hope I can pull this out and make this amp working and use it in my secondary system.
  9. Thank you very much. I just checked spec between the two and MJE15032G has higher tolerance in pretty much all categories. Would this be okay?
  10. Thank you very much. Yes, this is for learning a thing or two. I wish I have a friend who can guide me but I have no friend who knows about this stuff hence asking here. I might get a Variac for safety and testing purpose. This might be handy for this and future use I guess.
  11. Thank you. Yes, that is the plan of attack. I might eventually replace most of parts including adjustment pots and will start from BJT transistor which seem damaged and also all those power caps.
  12. Yes, I was testing in circuit.. (I must be too lazy) I completely took them out and measured again and here are the figures. 1st transistor from left (TR511) - B-C 0.308v, B-E 0.308v, Reverse C-B 0.319v, E-B 0.319v 2nd transistor (TR509) - B-C 0.048v, B-E O.L. Reverse C-B 0.048v, E-B O.L 3rd transistor (TR510) - B-C 0.529v, B-E O.L, Reverse C-B O.L, E-B O.L 4th transistor (TR512) - B-C 0.514v, B-E 0.536v, Revsere C-B O.L, E-B O.L If I understood meaning of these figures correctly, 4th transistor is ok but the rest of 3 are all bad. I am planning to replace all caps and transistors since they are all original and over 40 years old. One question. may I ask where I can get these modern alternative version of 2SD313D in Australia? I usually order caps from RS online but does not seem to have these BJT transistors.
  13. When I check the DC voltage output through speaker out is about 0.45v for both channels. I am not sure how much DC voltage out should be but seem very low.
  14. I found that these are NPN bipolar transistors and just did diode test and below are the measurement. 1st transistor from left (TR511) - B-C 0.175v, B-E 0.174v, Reverse should not have continuity but I got reading exactly same on opposite so C-B 0.175v, E-B 0.174v 2nd transistor (TR509) - B-C 0.045v, B-E 0.099v. Reverse are same C-B 0.045v, E-B 0.099v 3rd transistor (TR510) - B-C 0.505v, B-E 0.124v, Reverse are same C-B 0.505v, E-B 0.124v 4th transistor (TR512) - B-C 0.492v, B-E 0.121v, Revsere this time a bit different C-B 0.639v, E-B 0.124v If I understood correctly, reverse should not have reading and no continuity but both way have diode drop so it means that they are faulty?
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