Which deck to choose?

[KeithD]

Can you provide a link to the lamps you purchased from Parts Express? The problem you described could be caused by lamps that draw more current than the originals. If the lamps draw too much current, this could result in a power supply voltage drop that might affect other circuitry. Also, lamps that draw higher current can produce so much heat that plastic in the VU meters could be damaged.

Interesting. I did not buy the lamps from Parts Express, instead the guy I bought the deck from had some lamps on hand. He said they were 8 V, 30 mA lamps. I pulled both lamps out, and took just one of them and placed it in series with an ammeter to measure the current draw. With just the one lamp in, it was drawing about 80 ma. Also, I measured the voltage at the lamp terminals with no lamps in there, and the voltage being supplied read 9 V. I assume that drops under load?

Would 12 V lamps be better? The local guy has those as well.

Parts Express has LED axial lamps: https://www.parts-express.com/warm-white-3-led-axial-8-vdc-replacement-lamp-5-pack--070-144

 

[dhnash]

The 12V lamps would not be a bright as the 8V lamps and not knowing how much current they would draw makes it difficult to say whether this would eliminate the problem you are having. The axial LED lamps from Parts Express would probably be a better choice if they will fit in the area occupied by the original lamps since they will draw much less current than incandescent lamps.

 

[KeithD]

The 12V lamps would not be a bright as the 8V lamps and not knowing how much current they would draw makes it difficult to say whether this would eliminate the problem you are having. The axial LED lamps from Parts Express would probably be a better choice if they will fit in the area occupied by the original lamps since they will draw much less current than incandescent lamps.

Good point, the 8V lamps aren't that bright. They are ok, probably just right, but would not want them much dimmer. I also noticed the two 8V bulbs were not the same brightness, which makes me think they don't have the same rating.

What I really need (and no one seems to have ) is the service manual.

 

[dhnash]

A reproduction service manual is available from Rick Stout at Stereo Manuals (see the link below). It is priced at $23 plus shipping and the manuals I have purchased from him have all been excellent.

https://www.stereomanuals.com/man/rep/teac/teac_manuals_a-400_xx.htm

 

[KeithD]

A reproduction service manual is available from Rick Stout at Stereo Manuals (see the link below). It is priced at $23 plus shipping and the manuals I have purchased from him have all been excellent.

https://www.stereomanuals.com/man/rep/teac/teac_manuals_a-400_xx.htm

Thanks for the recommendation. I am still hoping someone has one they can share. HiFiEngine just has the user manual, no service manual.

 

[dhnash]

I think the manual that Rick has includes about 70 pages and 11” x 17” copies of the schematics. It seems unlikely that there are PDF copies of the manual available if HiFi Engine doesn’t have one but I suppose you can always wait see if one miraculously turns up.

 

[KeithD]

Obviously the service manual is out there, but no one has taken the time & effort to scan their manual and submit to HiFiEngine. I suspect that is because these decks are not very common. At this point, it does seem that site is the only option for getting an SM. Right now it would just be nice if I could tell what rating the original bulbs were. There was a post in this forum some years back saying the lamps are 8V and less than 100 ma. In that same discussion a member said he had the SM as a pdf, but that thread was 8 years ago.

The LED lamps at Parts Express are 25 mm long excluding the wires. I measured the distance between the soldering posts on the meters and it's pretty much the same distance, so it would be a tight fit for those LEDs.

 

[dhnash]

It might still be possible to fit the axial LEDs inside the VU meters by positioning the LED portion below the connection terminals and looping the leads up and back toward the terminals so they can be soldered to them.

 

[BilboBaggins]

Yes, it sounds to me like the two lamps are drawing too much current. Only thing that makes sense unless something was wired incorrectly. Have you thought about LEDs?

 

[KeithD]

After conact with a TEAC tech, these are the bulbs needed:

https://www.jkllamps.com/DA513?filter_name=Axial

The LED lamps at Parts Express should have the right ratings, but the length of the circuit board they mount on is the same as the space between the solder posts for the original lamps. I could probably make it work, but I've already ordered the JKL lamps.

I'll post when I've got them installed.

 

[twiiii]

If you want the best there is only one brand to consider. Nakamichi.

 

[KeithD]

If you want the best there is only one brand to consider. Nakamichi.

Had a Nak BX-125, but it had some kind of serious problem that distorted sound in a certain frequency range. Couldn't get help solving the issue. In the other ranges it was nothing special. I opened it up to troubleshoot, tracing the signal. I didn't see anything special in there above other decks I've had. It also became apparent from reading various threads that many Naks have known problems that need to be fixed to work properly.

Prices of Naks are high enough that I'm never likely to own another, especially since I have several decks that sound great to me. If the sound is comparable to CD, then do I need a "better" deck? I'm not going to toss $$ around just to get some perceived incremental "improvement." It's cassette tape after all. In some areas the Nak was inferior to the TEACs I have. No light behind the cassette so you can easily see how much tape is left. The printing on the face seemed to wear easily, and with an all black face, it can be difficult to see what the labels are. Without light shining right on the deck you couldn't see anything. Pale yellow on black is not a good combination. I know there are a lot of Nakamichi fans, and I say more power to them if you want to spend your audiophile $$ on that. I've got other priorities.

 

[SonofJames]

When I worked in HiFi at the DAT store certain Aiwa's were very well regarded as poor man's Nak's. But Nak was the best.

 

[kevzep]

If you want the best there is only one brand to consider. Nakamichi.

I'm sorry but I just cannot agree with this at all.....(he says with five Tascam 122 MKII decks)....

 

[KeithD]

New lamps with correct voltage and current rating installed. It really has a nice wood case!

 

[dhnash]

Glad the JKL lamps worked out well for you which was the first source I suggested back in post #16.

 

[KeithD]

Yes, thanks! Just to be clear, you need the DA513 lamp from that page (8 V, 55mA). There were several listed on the page you linked to, but I don't know that all of those would work.

 

[dhnash]

The difficulty in specifying which lamp would be the appropriate one for your application was not knowing the voltage being supplied to the lamp which is why I proposed measuring it. Fortunately someone else had this information and was able to identify the correct replacement lamp for you.

 

[skywavebe]

I may have been the source suggestion of the DA513 lamp- Do I use them? I just ordered 400 of them to make the point. They go into everything from Otari to Tascam and even other brands. The only trouble would be the Technics RS series that use a 5V supply and so a lamp called the DA403 was needed. I don't think they sell it anymore. Instead of guessing contact the guys who fix these all the time and even now and you will get the right answer. There are not big secrets on this- I tell people what I know all the time and sometimes they just don't like the answer but if they do listen they will have a working tape deck in the end.