thanks

I'll add one addendum to this exercise - if you add a large value resistor inline with the signal as I've shown here, you do have to contend with high frequency filtering in conjunction with the input capacitance of the amp. If the capacitance is very low, this is a minor issue. But if the capacitance is high (Miller capacitance in a tube amp, or in an amp that has an input cap added in shunt to the input, something in the order of 100-300pf for example) you will create a low pass filter that will restrict bandwidth and roll off the high frequency response. The bad-er news: a volume pot will do the same thing unless it's low impedance like 10k to 50k max, while also messing up the input impedance of the amp. Everything is a compromise, the only way to "correctly" fix too much sensitivity involves redesigning the input stage of the amp or the ouput stage of your preamp to reduce the gain. So pick the method that does the least harm.

I am continuing to work on a Nakamichi Dragon ( serial number 21XXX ). The cam motor continues to run while in play forcing it to the most counter clockwise position. The VR 603 play pot does nothing in play mode. The VR 603 and cam pot are good. When I first received it the 1amp fuse was blown. I found a bad 1000uF 16v cap. I recapped the logic assembly board. It powered up and the display and transport worked. Transistors Q516/616 are good. The IC603 opamp which feeds the bases of those transistors is putting out 10.14v at pin 1. I was thinking maybe there is bad logic chip that is causing the malfunction? The cam motor continues to run when it should stop after performing each transport function. In stop mode it the cam motor does stop and allows the arrow mark to line up with pointer while adjusting VR 604.

من هم یکی از این مدل دارم که با هیچ چیزی ان را عوض نمیکنم و میخواهم تا اخر عمر ان را نگه دارم 🇮🇷

Good afternoon. I have the same one but one of the motors is failing, the spare part no longer exists, could you tell me the characteristics of the same one so I can find an equivalent one?

what are the white coupling caps you used? Believe the stock caps were SCR, not the greatest sounding cap. tks

thankyou!,good concise and valuable info, made easy enough to grasp the essential application..😇👍

I have a Revox B215, and its mechanics are on a completely different level. One motor for each movement, no belts, no idlers, no plastic parts, and no auto-alignment system with performance that drifts over time. I feel like buying a Dragon just to prove my point about a machine made of a thousand plastic parts that everyone places on a golden pedestal.

if i had that deck i would just disable autoreverse completely.

exotic AF

just asking as complete noob,,, osc. probe is x1 or x10 set ?! Thanks

my SU-V303 shows Newclass A but the Computerdrive sign remains off, what does this mean?

JASON from Calgary. Canada's version of Jordan Pier.

Tip is valuable but should have been filmed to a higher standard

I have an SLA-30, and my lord, what a design direction change.

Correction: the 2 rectifier tubes are run in parallel, not series.

This is the stereo version right? It must be: everything seems to be doubled...

That technique has been used for decades....

Good tip! Thanks for posting this.

I just saw an ad on "fixing your poop" twice while watching this video.😂

how strange, mine is identical but it's called SU V 505. (??)

Sorry to say it but what a lot of nonsense. 12 output tubes?

terrible noodle work

Ya thank you captain obvious............how about the sealed pot to the left of the super easy one you just did ?

7:30 Member if the head is aligned for one side, both sides are aligned 90 degrees. So it means the 4-track head is ALIGNED both sides.

how many capacitors does this amp has,do you have any recommendations for an upgrade to bust the bass?

Nice … as I’m watching it adjust back to flat I’m think a few moments latter…

Vintage beauty 😍

The thing is now. Alcohol or Caig Fadr cleaner. I have had good luck with both.

Nicely explained

You must have an open ground on your scope probe to get that kind of deflection.

Can u explain how to change the bulbs?

I am getting the exact same reading regardless of which way capacitor is connected. Ive tried three different types of non polar capacitor including one you showed in vodeo I am not getting any difference at all

How can I get in touch with you? I have a ps-f9 that need the clamp mechanism rebuilt and I have the new gears.

I've never been able to reproduce these results... probably my own fault for not knowing how to use my o-scope.

When I was a little, our neighbor had one of these... I absolutely loved it... Have been hunting one fir years.

Really nice. I love my Dragon but, as my other decks, I would never service it myself. Too scared 😂. But the sound is awesome even after over 30 years

Hi!

Thought the whole idea with alps sealed pots is that they are dust proof

Can you open a Sony playstation

If this mattered, it would be on spec sheets

For me, since I don’t have the skills, expertise, or Nak testing tools to repair a Dragon, simple 3 head Sony’s are the best option. They make excellent recordings and you can buy a bunch for the same price as one Dragon.

I remember this one... It also has a FM transmitter to listen to the record straight from the Radio

What do you consider exotic? It’s a cassette deck that automatically adjusts its playback heads, has double locked DD capstans that both switch directions for both sides of the tape, two tape counter mechanisms, and an entire circuit board that runs a little motor that controls the alignment of said heads. I’d say it’s a little more exotic than a plunger solenoid slapping against metal and an Single idler tire running the show in most decks.

I changed the little belt on the drive motor thanks to you. Tysm! Couldn't have done it without this great tut.

I thought that the height moves the head front to back and forth. Height term remained from the days of top loading decks.

You need to set the icq frequency to 400khz using a counter

So how would I solder a tone cap on a guitar once I have this information?

Helpful video thanks. Finally got a pot on my phono preamp clean that had been driving me nuts for years

Just before you mentioned the hairline crack, I said to myself - 'there'll be a miniscule crack in the tracks'. Like looking for a needle in a haystack! The best systems are modular design, but I guess we have to pay the extra them.