Simplistic NJFET RIAA

Jump to Latest
#2,882
We know for instance that R input 10R saved off half of Ricardo's vdiff at a little over 200mA... Hard to predict. I suggest you get air coils about 1-2R from speaker vendors, some mH, and make CLC. Will help, but will not be drastic with voltage drop.
 
#2,883
Just replaced the 10r 5w by 2r2 12w and the sound regained the lost transient attack.

I am now playing with TX placement inside the case.... The best seems to be both TX at one corner standing on its sides.
 

Attachments

  • DSC_0227 vsmall.jpg
    DSC_0227 vsmall.jpg
    298 KB · Views: 392
#2,887
The French relabeled Indian guy just made it to arrive in 2009.
The OEM factory is a rather good one and says the core is grain oriented. Has an electrostatic screen too. 11x9x5cm LWH for 120VA.
 

Attachments

  • R1.JPG
    R1.JPG
    148.4 KB · Views: 363
  • R2.JPG
    R2.JPG
    162.7 KB · Views: 354
#2,888
Indian? They were supposed to be "made in china", weren't they?

I also got my "made in china" (clearly labelled) split bobbins Hammond 229 for DCB1.... 🙂

BTW, I'm in doubt how to orient it to get the minimum hum.... I guess I must show the iron, not the coils, to the pcb, am I right?

Καλì Χρòνια
 
#2,889
We figured out OEM, but its not China in the end. I see Indian electrical factory on the bobbins and on back of its base. So its different than the ones on Ebay.

For the Hammond I don't know from experience with it, but the corners should be most offending. I would try in length and perpendicular to the board. Happy new year to you too. :cheers:
 
#2,890
The company is a well known manufacturer in india - he had japanese collabration meaning very tight quality control from the early years. Surprisingly they started manufacturing R-core transformers first.
how does the cost compare to the ones on ebay from hong kong?
kannan
 
#2,892
kannan_s said:
The company is a well known manufacturer in india - he had japanese collabration meaning very tight quality control from the early years. Surprisingly they started manufacturing R-core transformers first.
how does the cost compare to the ones on ebay from hong kong?
kannan
Click to expand...

The list cost is good. 36 Euro for 120VA. I just saw a 100W Chinese one on e-bay for US$45. Bad thing is they don't arrange careful shipping costs within Europe at least. They used a box that it could take a tanker ship inside in my case. Could have been 1/6th the volume easily. The Indian factory looks learned. Here is their page about the R-Core they make.
 
#2,896
Honestly I have at home a pair of similar R core from Selectronic, but I never thought to google the name on the bobbin support!
Chapeau, Kirie Salas!

P.S. Are you going to eat Vassilopita tonight or tomorrow? 😉 Good luck!

We must organize a mini GB in France for more R cores in the future! I have some ideas.....

Hey Nicoch, you might have some experience with the Hammond 229 as, if I'm not wrong, you used it in the past: how should I have to orient it pcb wise to get the minimum noise?
 
#2,899
Happy new year Ricardo!

I will power the genuine low MC build that I am collecting parts for. 2X21 in series will give me ample voltage to experiment. I would get less VA, but 2X21 starts at 120VA in that French list.
 
#2,900
massimo said:
Honestly I have at home a pair of similar R core from Selectronic, but I never thought to google the name on the bobbin support!
Chapeau, Kirie Salas!

P.S. Are you going to eat Vassilopita tonight or tomorrow? 😉 Good luck!

We must organize a mini GB in France for more R cores in the future! I have some ideas.....
Click to expand...

I ate and drunk and went out to clubs alright.🙂

P.S. If you dig deeper you will find that the ex works export price list starts at 10pcs minimum.😉 Are you ready for Rupees, Italian bank, sea transport company FOB arrangements and customs clearance?😀
 
You must log in or register to reply here.
Top Bottom