back and front are very thick, and looks like they house the fans
anyway, its massive heatsinks
looks great, inside
Any current device marked Hitachi is probably a fake...
Renesas is the merging of Hitachi and Mitsubishi semi dpts
as specified in this PDF...
Luke,
neither the PMF-5150 nor the PMF-5550 has a fan. (but the company loves to stick fans in amps.
)Both models use Hitachi 2SJ56/2SK176 devices.
125W Pd each, times 12 makes a total Pd of 1500W.
Both are 500W/ch models, 1500W Pd divided by 500 makes 3.
(both amps had 100Vdc rails, which was not very wise for 200Vds devices)
Luke,
neither the PMF-5150 nor the PMF-5550 has a fan. (but the company loves to stick fans in amps.
Both models use Hitachi 2SJ56/2SK176 devices.
125W Pd each, times 12 makes a total Pd of 1500W.
Both are 500W/ch models, 1500W Pd divided by 500 makes 3.
(both amps had 100Vdc rails, which was not very wise for 200Vds devices)
All the pro amps they made had fans. Not Hifi models.
They claimed the 5550 can deliver 1500 watts per channel, I cant really remember. I know it can run all day long delivering 1000 watts/ch. All the older pmf amps delivered twice the rated power into 4 ohms continuous. I had a 3350, and the baby 1050 which I still have. The 3350 I regret selling.
Luke,
That interior shot has a nice uncluttered housing. Very neat and organized.
I thought that Renasas and Hitachi devices were made at the same location with the original equipment and spec. The only thing that different was the companies merged and the name changed. Even when Hitachi was branding there name on the devices that did not mean they were manufactured in Japan in there plants. Stuff from good reputable companies is outsourced all the time to save labor costs and take advantage of low bidding. I mean is On Semi transistors really that different than an old Motorola transistor.
I have for quite sometime wondered if the Toshiba j109bl jfet fakes were really, spec wise, that terribly bad. Any company that can tool up to manufacture semiconductors must realize the initial cost to begin production is way to large to just sell outright junk. Just because someone is stealling your name does not necessarily mean they are going to abuse it. It may be to the contrary to continue profitting by making acceptable merchandise.
Tad
That interior shot has a nice uncluttered housing. Very neat and organized.
I thought that Renasas and Hitachi devices were made at the same location with the original equipment and spec. The only thing that different was the companies merged and the name changed. Even when Hitachi was branding there name on the devices that did not mean they were manufactured in Japan in there plants. Stuff from good reputable companies is outsourced all the time to save labor costs and take advantage of low bidding. I mean is On Semi transistors really that different than an old Motorola transistor.
I have for quite sometime wondered if the Toshiba j109bl jfet fakes were really, spec wise, that terribly bad. Any company that can tool up to manufacture semiconductors must realize the initial cost to begin production is way to large to just sell outright junk. Just because someone is stealling your name does not necessarily mean they are going to abuse it. It may be to the contrary to continue profitting by making acceptable merchandise.
Tad
Only Lateral MOSFET amp company i've seen that ran such big hurds of output devices without source resistors.
Both the 100W and 125W devices (J and K) are rather easy to match, see Juma's thread for an example : simple cirklotron with Lateral MOSFETs.
(Japanese parts that have Japan printed on them in general are/were manufactured in Nippon, blanks are/were made somewhere else)
Both the 100W and 125W devices (J and K) are rather easy to match, see Juma's thread for an example : simple cirklotron with Lateral MOSFETs.
(Japanese parts that have Japan printed on them in general are/were manufactured in Nippon, blanks are/were made somewhere else)
I use three pair/channel matched 2SJ48/2SK133 without source resistors..
True that i m not a company...
I ve seen it done in a german amp that did use these same devices..
Hello
First:
Those are not current produced device! I purchased at local store in Toronto where only sell orig parts !
Second:
I compared with orig Renesans purchased from MCM electronics
Huge difference in favor the Japanese Hitachi sound wise😀
Third
That is not regular paint , I tried to wash done with Acetone , paint remover etc , nothing happened.
I'm sure those are not Chinese "FAKE" devices. Not Ebay product!
-I have very old parts 2SC1775 & 2SA872 with white mark (same as these Hitachi)
You can still get orig Hitachi 2SK1058 some places
for example Pacific Semiconductor, but another places to.
Fourth:
It would be very interesting if the fake gave better sound than the orig Renesans product , or not???
Before I purchased a lot it was tested thoroughly. It cost me more than double than the Renesans.
I purchased laser graved 2SK246GR 40PC and garbage , I tried to match them and impossible , at the end I thought check if I can measure hfE , but nothing!
Greetings
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Hello
These 2SA872 is a very old device (white painted) !
I sold over 100 M Hiraga kits 5-6 years a go with out any complain .
If it would be current production that would be counterfeit , some of these parts I have 8 years or more . Some of them I took the out from used amplifier!
These 2SJ162 used part! Same as I posted before.🙂
Greetings
These 2SA872 is a very old device (white painted) !
I sold over 100 M Hiraga kits 5-6 years a go with out any complain .
If it would be current production that would be counterfeit , some of these parts I have 8 years or more . Some of them I took the out from used amplifier!
These 2SJ162 used part! Same as I posted before.🙂
Greetings
Attachments
Albs MOS modules.
Don t know thoses ones..
Was an obscure brand, Profmos V2000Q..
Perhaps it was the modules you quoted, who knows.
Hi Alex, the original relay was a fast switching Panasonic JN1A-TMP-DC24V. It's a 24V, 30A relay. I found this online, but that's all the info I have: http://download.siliconexpert.com/pdfs/2006/10/03/pemco_b/1/mew/power relays/mech_eng_jtn.pdf
Maybe someone can jump in here and recommend something, but I think any PCB mount fast switching, 24V, 30A (or close to it) relay will work just fine.
Maybe someone can jump in here and recommend something, but I think any PCB mount fast switching, 24V, 30A (or close to it) relay will work just fine.
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Also Alex, in your schematic:
D4 and D6 should be 1N4002
R25 should be 0.22, 3W
L1 should be 22T Moulded
Also, the series inductor L1, resistor R25 and the Zobel R24, C6, C7 are part of the amplifier, I just drew those in to make it easier to see where the protection circuit connects to. Just in case this is a little unclear.
D4 and D6 should be 1N4002
R25 should be 0.22, 3W
L1 should be 22T Moulded
Also, the series inductor L1, resistor R25 and the Zobel R24, C6, C7 are part of the amplifier, I just drew those in to make it easier to see where the protection circuit connects to. Just in case this is a little unclear.
Hey - go easy on Alex!!! He jumped in and volunteered a bucha work - buuuuuuut dis is getting a little crazy!!!
NagysAudio:
Please Please explain the difference between 1N4004 and 1N4002 diodes, or am I mistaken about the correction you are suggesting?
I never suggested such a correction, so I'm not sure what you mean. The D4 and D6 were simply not labeled in Alex's protection circuit schematic and they should be 1N4002.
To answer your other question, 1N4002 is a 1A, 100V diode and 1N4004 is a 1A, 400V diode. In this schematic either one works fine and makes no difference.
To answer your other question, 1N4002 is a 1A, 100V diode and 1N4004 is a 1A, 400V diode. In this schematic either one works fine and makes no difference.