Archived from groups: rec.audio.tech (
More info?)
Tim,
thanks again. i don't use my real email for privacy/security reasons.
i will email you assuming that your email is a valid one.
now i can make my trip to Radio Shack...
On Tue, 20 Jul 2004 12:04:12 GMT, Tim Schwartz
<toschwartz@worldnet.att.net> wrote:
>PizMD,
>
> First, please use a valid e-mail address in you postings.
>
> The info that I gave you about F1 and F2 being 1A fuses is from the
>service manual. It is possible that the fuses in you amp were changed
>at some point with the wrong fuses. Less likely is that the factory
>changed the spec, or an error was made during manufacture.
>
> The voltage rating on fuses is only a rating to stop arcing in the case
>of a blown fuse, so it is always safe to use a 250V fuse in place of a
>125V fuse, but not the other way around. on the assumption that you
>live in a 125V line voltage area, 125V fuses would be fine, as would
>250V ones.
>
>Regards,
>Tim Schwartz
>Bristol Electronics
>
>
>PizMD wrote:
>>
>> Tim,
>>
>> thanks a mill. based on what you have indicated, are the 1A fuses
>> 250V as well? why would there be 4A fuses in F1 and F2?
>>
>> the fuses blew because i did something foolish and had my otherwise
>> wonderful device hooked up to a large PA speaker. i do not know what
>> rating of the speaker was, but i had no business doing it. it
>> actually held up quite well under the circumstances. when i put the
>> amp back in my office/studio, i noticed an obvious degradation in
>> sound. i decided to fix it myself this time instead of putting out
>> $85 as i did the last time it went on the blink.
>>
>> although i have a copy of the original user manual, i did not realize
>> until researching for this repair that this amp is only rated at 30W.
>> i have no idea how i missed that important fact. i have done a few
>> thing with this amp that should have killed it long ago. i have had
>> it for going on 10 years and it was used when i got it.
>>
>> anyways, any further assistance you can offer is greatly appreciated.
>>
>> TIA
>> On Mon, 19 Jul 2004 12:08:38 GMT, Tim Schwartz
>> <toschwartz@worldnet.att.net> wrote:
>>
>> >PizMD,
>> >
>> > According to the manual, all 4 fuses are slo-blo or 'T' type. F1 and 2
>> >are 1 amp and F3 and 4 are 4 amp. F1 and F2 power the regulated
>> >supplies that feed the preamp and power amp, where as F3 and F4 are the
>> >unregulated fuses for the rail that supply only the power amps.
>> >
>> > If a second set of fuses blow then you have another problem. It is not
>> >rare for an older NAD like this to have soldering problems and 'cooked'
>> >small electrolytic capacitors that have dried out, especially near
>> >sources of heat like the power supply regulator transistors.
>> >
>> >Regards,
>> >Tim Schwartz
>> >Bristol Electronics
>> >
>> >
>> >PizMD wrote:
>> >>
>> >> i want to repair my amp, but i don't have enough technical
>> >> information. 2 fuses blew and i am trying to figure out if the are
>> >> slow or fast-blow and what arrangement the fuses actually should be in
>> >> on the board. the fuse attachments are marked F1, F2, F3 and F4. all
>> >> of the fuses are 4A 250V, but 2 have BUSS AGC on them and the other 2
>> >> have 313 on them. the ones that blew are the BUSS AGC.
>> >>
>> >> 1. is there a difference between these 2 sets of fuses? (slow/fast)
>> >> 2. if there is a difference, which fuses should be in which spot?
>> >> (F1,F2,F3,F4)
>> >> 3. is there a service manual/schematic available?
>> >> 4. could someone make this info available to me?
>> >>
>> >> TIA
>> >> PizMD
>> >>
>> >> HUMANS: the animal that killed the planet...
>>
>> PizMD
>>
>> HUMANS: the animal that killed the planet...
PizMD
HUMANS: the animal that killed the planet...