Service manuals, schematics, eproms for electrical technicians

HOWARD RADIO CO. HA-2 SCH

AUDIO - SERVICE MANUAL
Type: (PDF)
Size
49.5 KB
Page
2
Category
AUDIO
SERVICE MANUAL
If you get stuck in repairing a defective appliance download this repair information for help. See below.
Good luck to the repair!

Please do not offer the downloaded file for sell only use it for personal usage!

Looking for similar howard manual?
Advertisements
Document preview [1st page]
HOWARD RADIO CO. HA-2 SCH service manual (1st page)
Preview of HOWARD RADIO CO. HA-2 SCH [1st page]
Click on the link for free download!
Document preview [2nd page]
HOWARD RADIO CO. HA-2 SCH service manual (2nd page)
Preview of HOWARD RADIO CO. HA-2 SCH [2nd page]
Click on the link for free download!
Advertisements
Please tick the box below to get download link:
  • Also known:
    HOWARD RADIO CO. HA-2 HA2 HA
  • If you have any question about repairing write your question to the Message board. For this no need registration.
  • If the site has helped you and you also want to help others, please Upload a manual, circuit diagram or eeprom that is not yet available on the site.
    Have a nice Day!
  • See related repair forum topics below. May be help you to repair.
Warning!
If you are not familiar with electronics, do not attempt to repair!
You could suffer a fatal electrical shock! Instead, contact your nearest service center!

Note! To open downloaded files you need acrobat reader or similar pdf reader program. In addition, some files are archived,
so you need WinZip or WinRar to open that files. Also some files are djvu so you need djvu viewer to open them.
These free programs can be found on this page: needed progs
If you use opera you have to disable opera turbo function to download file!
If you cannot download this file, try it with CHROME or FIREFOX browser.
Translate this page:
Relevant AUDIO forum topics:
repair sony amplifier str-de254
Want to share: Have downloaded the schematics from this forum to help repair the amplifier of a friend. Turned out that Sony decided to route the earth through the chassis, even the earth between the various supplies. When one takes the main board out of the chassis and switches the amp on, there are up to 20 volts difference between the eart (and hence reference) of the pre-amps and the main amps. Luckily the amp goes into protection but from a design point of view it is not nice to rely on screws and aluminum face plates to conduct up to 0.2 amps of current from one supply to another. What I did is solder wires to every eart point and connected them on the main board to make it stand alone and not rely on conducting current through the chassis anymore. Bad design, simple repair but took some digging in the schematics to find out what exactly was going on!
ION Archive LP Turntable

This is a compact design to I guess transfer the vinyl into MP3 format.
Complaint was when the arm was moved the tt dont spin, confirmed that as
theres a leaf switch to sense arm movement,
and its fed to a main pcb with all the IC's that I guess handle all the
stuff. The switch is ok, and I remember seeing 14V or so on the motor pins
frm the PCB, so I figured perhaps theres anough current to spin the motor and
focused on testing the motor.

Manufacturer does not supply the mainboard that feeds the motor but
the motor can be taken apart and after I opened it and
disconnected the small pcb fron the motor terminals and apply power
directly, it spins w 12v. theres a small electrolytic cap on the pcb 25V / 22uF and an
AN6652 4 pin T0-220 type case IC that I guess is some kind of speed control
circuitry.

The drive Motor is an EG-530-SD-3F, main board is stamped K-13007.
Gonna check the cap, but after searching this IC and its
applications with the motor, I see its popular and some drawings show how its used to regulate the 78,33
and 45 rpm speeds.

This drawing looks pretty much what I see in there:
https://tectronelectronics.eu/images/thumbnails/465/465/detailed/31/eg530.jpg
 

I have replaced the IC and the cap, but the motor still does not turn. The main pcb

is proprietary and cant be purchased, and I think it is giving the op-amp IC a reference signal.

Is there a way to bypass that signal or fool the IC to believing its on to test it out?

Photo showing the motor pcb :
http://www.mediafire.com/view/s79blgku1503mtg/HPIM0643.JPG/file
Photo of motor under test:

http://www.mediafire.com/view/thhgvcwac8al7gu/HPIM0635.jpg/file

 

 

 

Marantz CD 73 Hang Hiba
A barátom cd játékosa került hozzám nemrég, a sztori úgy indult hogy egyszer csak elhallgatott és se kép se hang, ennek 5 éve most elhozta hogy kukkolja már bele mi lehet a nyűgje, első bizti csere mivel ki volt égve, aztán ráköt a hifire és csak ilyen sercegéses zúgás tör elő belőle, cd bele olvas mindent, de a zene mellé párosul ez a búgó zúgó hang mintha test hiánya lenne de ezt átnéztem és minden rendben, ötleteket szivesen fogadok. Egy kis videó arról hogy mi a hiba:
PANASONIC SA-AK210 HIFI torony javítása
Sziasztok!A fenn említett hifi-menet közben kikapcsol(csak a CD-t használom)-egyáltalán nem lehet bekapcsolni-híbákkal küzd.Kérem tanult kollégáim sagítségét!Köszönöm.Jano
Similar manuals:
If you want to join us and get repairing help please sign in or sign up by completing a simple electrical test
or write your question to the Message board without registration.
You can write in English language into the forum (not only in Hungarian)!

E-Waste Reduce