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Replacement for SRF3999 RF power MOSFET?

P

pdmtr

Jan 1, 1970
0
Hi
Does anyone knows a replacement equivalent for the MOTOROLA SRF-3999
RF MOSFETs?
Thanks in advance
Sotiris
 
M

Michael A. Terrell

Jan 1, 1970
0
pdmtr said:
Hi
Does anyone knows a replacement equivalent for the MOTOROLA SRF-3999
RF MOSFETs?
Thanks in advance
Sotiris

'SRF' are propritary part numbers, custom marked for their customer.
BTW, Motorola is no longer in that business. On Semiconducotr took over
those lines years ago.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
P

pdmtr

Jan 1, 1970
0
'SRF' are propritary part numbers, custom marked for their customer.
BTW, Motorola is no longer in that business. On Semiconducotr took over
those lines years ago.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Hi
Yes I do know that, but all SRFs was common commercial transistors and
I do remember that there was a list available with the equivalent,
back at 80's. I had such lists, but after 3 lab moves many papers have
been lost ;(
So anyone knowing what was the SRF3999 on a commercial available P/N?
Thanks in advance
Sotiris

PS These were used at 150W P-P RF amplifiers to HARRIS FM
transmitters, if that helps to wake up memories ;)
 
F

Franc Zabkar

Jan 1, 1970
0
Hi
Yes I do know that, but all SRFs was common commercial transistors and
I do remember that there was a list available with the equivalent,
back at 80's. I had such lists, but after 3 lab moves many papers have
been lost ;(
So anyone knowing what was the SRF3999 on a commercial available P/N?
Thanks in advance
Sotiris

PS These were used at 150W P-P RF amplifiers to HARRIS FM
transmitters, if that helps to wake up memories ;)

I have a 1984 Motorola master selection guide. The only RF Power FETs
with a 150W power spec are MRF140 and MRF150. MRF174 is rated for
125W. The first two are characterised at 30MHz, the latter at 150MHz.
All but the MRF150 (50V) have a Vdd of 28V. The case style is 211-11
(0.500 flange).

http://www.datasheetarchive.com/datasheetpreview/DataBooks/Document249111.jpg
http://www.datasheetarchive.com/datasheetpreview/DataBooks/Document249215.jpg

- Franc Zabkar
 
P

pdmtr

Jan 1, 1970
0
Hi Frank
Thanks for the suggestions but these are case style 316-01 (more like
the MRF317 transistors), working at 28Vdc (although the PSU can be
adjusted up to 32Vdc !? ). I do have all of the Databooks from Moto
since late 70's until even after the name turn to "ON semic" (at
first, now at Macom & Freescale) and have tried to find similarity to
RF MOSFETs for them, without any luck! The original HARRIS transmitter
circuit schematic has them as MOSFETs, but I'm a bit sceptical about
them, as the topology, connections and the circuit itself, seems to
have been designed for common RF transistors... ie no +Vg bias
circuit, just a 10 Ohm grounded resistor from the gates! Probably
class C circuit, but I can't remember any Moto's MOSFET having that
case style (316-01 6lead flange planar)! Thought to ask here as there
was times that an SRF to MRF chart published periodically from Moto,
and maybe someone still have them to give a look... :(
I might try to put the MRF317 ! instead of some MOSFETs as the RF
output power levels, PSU and the onboard broadband transmittion line
input/output matching section looks quite similar (if not say as
exactly same) with those used with the MRF317s!
However thanks everyone replied to my quote...
Regards
Sotiris
 

arthie

Nov 3, 2009
1
Joined
Nov 3, 2009
Messages
1
I test with two 2SK317, this is a power mosfet of 120 watts, and works fine this solid state IPA. Only with 200 Watts is enough.

Arthie, Mexico City
 
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