[Sir Tmotts III]

Hey all. My first amp was and is my NAD 3020. poor baby needs help though. her left channels just isn't there anymore , and the phono pre-amp dosen't work either. So if i could fix the amp up, it would be nice to say the least. but i haven't a clue how to fix it or where to fix it.

 

[duncan1]

This amp was very highly thought of in the 1980s in the UK .It has "soft clipping" and the sound reproduction was smooth if it sounds harsh then its  faulty. Funnily enough  bought one last week at what is called here a car boot[trunk]sale which are like garage sales but 100s of cars open their trunks and sell goods  at an event [usually every fortnight] . My 3020 cost me $24 I haven't tried it yet but outwardly looks okay the seller knew what he was selling as these amps are collectible now[so don't undersell it] because they sound very like "tube sound"-smooth.
     If you get it working and like tubes you will like it. The amp and pre-amp are separate and connected by phono/RCA leads . The output BJTs are 2n3055 and MJ2955 The good news is that it is all discrete[no chips] so is easily fixable. Check all 4 fuses on the board for  continuity and check the output BJTs for S/C .If you have test gear input a signal through each power section in turn and if as you say one channel is down it is likely to be the power BJTs in that channel . They are easily replaced just unsolder put new one in[they are very cheap to buy] along with a new mica/plastic insulator. If you have a MM with a transistor tester built in -attach wires to the removed   bjts and push them into the tester socket . The gain will be very low but that is normal for them . Get back if need any more info. Just like to add took off cover of the nad 3020 and checked fuses they are okay been lying in some loft for many years filled with dust left on for an hour all four output  BJTs  heated up good sign get out test gear tomorrow and check .

 

[duncan1]

Well I was right! clicked on NAD 3020 for sale got a few up -Highly thought of etc -guy in Dublin -Ireland just sold one for 50 Euros which probably is $70 or so. Even if it doesnt work repair it it wont go down in value only up.  Click on Steve Guttenberg in C/NET news he gives it a glowing report  "better than many modern amps" But watch out for script virus I got hit by 2.[blocked]

 

[duncan1]

My "boot sale" NAD 3020 works just fine smooth and tube/valve like maybe too smooth for me but it will certainly please those who like "tube sound" Its no surprise it sold in 10000s  here in the 80s VERY popular and a good write up from the "Golden Ears" If you input a signal to each power amp input[pre amp has separate inputs] and turn the volume up you should see the power[watt/8ohms] LEDS light up as you progressively increase the volume. Although it is nominally =20W/ channel this amp can go much more into a lower impedance MORE than doubling its output. This was well liked by the hi-fi mag gurus. as it showed it wasnt a "limiting amp" Small size big power If you get the chance of it cheap buy it.