Realistic STA-2100 (ReCap)

[Super Noob]

https://drive.google.com/open?id=1A6FZ4NnxqyNGD_11rUcYS2kWawSJGfxI

Here is my verified list of lytics, relays, and trimmers. Parts ordered. Note I do order a few extra of caps = sometimes the price break just makes it a no brainer.

I will post the results. I have two (2) 2100 (non-D) models, and the parts are slightly different than the 2100D.

Anyways = this may save someone time the future.

Best Regards.
NOOB

 

[Super Noob]

Okay - here comes some update (multiple) posts.

LED Upgrade.

Fuse lamps were straight forward. The dial face required some modifications to get the lamp to seat at right height. Function indicators were a bit challenging too. Anyways - satisfied with the results.

 

[Super Noob]

Tone Control Board

Before:

After:

Dexoit on all pot contacts.

 

[Super Noob]

FM / Tuner Board:

Before:

After:

 

[Super Noob]

Power Supply:

Before:

During (Heavy Glue):

After:

 

[Super Noob]

Relay Board:

(including new relay)

 

[Super Noob]

Protection Board:

Before:

After:

 

[Super Noob]

Selector Board:

Before:

After:

 

[Super Noob]

Main Amp Boards:

Before:

After:

All transistors with heat sinks were re-pasted (including outputs):

 

[Super Noob]

Main Power Caps:

(2.2uF bypass caps)

 

[Super Noob]

Old Parts:

 

[Super Noob]

First Listen:

Bias on outputs (dead nuts):

Here are the pics = https://photos.app.goo.gl/ZveqwiZ8ZLhY9ESM8

 

[NAD80]

Welcome to AK. Great job. Main question is how does is sound? And what are the speakers your playing thru?

 

[Super Noob]

NAD 80 - rebuilt to gift my father-in-law... have another 2100 (that will be rebuilt).

STA 2100 is underrated for sure... the Realistic tags hurts it.

The build inside it solid and is easy to work on.

My work area has OLA (original advents - rebuilt last year fresh foam and caps) and JBL-36. Pushing the OLA... sound great. 120 WPC provides for plenty of dynamic headroom.

Honestly sounds just as good as my other receivers... and I have a couple (okay maybe more than a couple).

 

[NAD80]

I think you will make his day with that 2100. Good luck with the other.

 

[craig elder]

https://drive.google.com/open?id=1A6FZ4NnxqyNGD_11rUcYS2kWawSJGfxI

Here is my verified list of lytics, relays, and trimmers. Parts ordered. Note I do order a few extra of caps = sometimes the price break just makes it a no brainer.

I will post the results. I have two (2) 2100 (non-D) models, and the parts are slightly different than the 2100D.

Anyways = this may save someone time the future.

Best Regards.
NOOB

This is my first rebuild. I appreciate the list you made. I am making an updated excel sheet listing all the parts and which ones are on each board. I am then sorting all the values so a person can know how many of each will be required. Do you have any other updates for the transistors? How do you set the new trimmers on all other boards except the amp boards?. I have not done this before. When you replaced the two large relays, which pins did you break off, since it only uses 6 of them? Have you heard of anyone changing out the carbon resistors with metal oxide Ohmite resistors. Do the wire wound have any issues? I wanted to change these in the main amp, preamp, and tone boards. Do you think it is worth it? I know how to set the bias and dc offset after the caps are changed. Can you get rid of some of the ceramics because of the noise issues? I noticed you used mostly Nichicon. Are the Elna better for the audio caps? I am also changing the full wave bridge ahead of the main caps. I will be using hexfred with a recovery time of 23 ns.They are both soft and fast recovery. Very low noise. Take a look at the specifications.https://www.mouser.com/datasheet/2/427/vs-hfa15tb60-m3-1351136.pdf They did not have full wave bridge for what I wanted, so I just am using 4 of them to build the bridge. I will show you how I attached them later. I used Nichicon super through 15000 uf, 80 volts for the main caps, I did not want to go to a larger value because of the stress it might put on the transformer. They are way bigger than the old ones. 63 mm x 100 mm. I was looking at a theory book and it said I should be using 24000 uf per rail per 100 watts. I am not quite sure why the design engineers used such a low value, other than 15000 was enough to smooth the waveform. These were the cheap parts, they cut corners somewhere.

 

[Super Noob]

Relays Changed = Yes
Only Bias & Offset Trimmers Changed.
No Transistors Changed.
You could change small transistors if you like.
You could change ceramics if you want.

I like Nichicon... have started using Panasonic general FM series recently for non signal and non power supply. It is just personal choice.

Just use filters for the caps value on excel makes it easier. FYI - I am just a hobbyist.

 

[jheu02]

Lots of work. Hard to tell from the pics as they are rather small.

 

[Super Noob]

Lots of work. Hard to tell from the pics as they are rather small.

I have done this set twice.... double the fun.

http://audiokarma.org/forums/index.php?threads/project-sta-2100-realistic-2.834575/

It has larger pics.

 

[antpaubarcar]

Hi Guys,
I like the STA 2100 very much and I am planning to get one but I have a big doubt that maybe you can help me with: is it possible to have it running on Ac 220v without a transformer, just changing something on the power suply board??