Mitsubishi RF power module substitute. - UK Vintage Radio Repair and Restoration Discussion Forum

G6Tanuki · 9th Jul 2025, 11:44 am

The flat Mitsubishi RF power modules used in a lot of 80s and 90s Japanese VHF ham transceivers are known to be prone to failure and genuine Mitsubishi ones are long since unobtainable, presumably because the stock has been used up to replace failed ones!

I noticed that Moonraker and Waters&Stanton are now listing a Toshiba part, SAV7 - as a replacement for the Mitsubishi M57733.

Price £25. No experience of actually doing the swap, the Mitsu block in my Trio-Kenwood TR-7800 is still working OK, but it's interesting to see that if it does die there is a suggested replacement.

Note that this is a Class C amplifier and so no good for replacing the Class AB or Class B modules used in similar-era multimode transceivers.

I would prefer to buy from someone like W&S than take a chance on getting a part from one of the far eastern online shops.

Terry_VK5TM · 9th Jul 2025, 10:11 pm

Alternative Mitsubishi RF modules are available.

RA08H1317M RF Module 8W 135-175MHz

RA30H1317M1 RF Module 30W 135-175MHz

RA60H1317M1A RF Module 60W 136-174MHz

its ur aerial · 12th Jul 2025, 8:27 am

Thanks that's well worth knowing,
Ken G6HZG.

AdrianH · 12th Jul 2025, 10:03 am

If use to anyone to play with I have a few RA07M131M modules left over from my working days, I doubt I would get to use them now.
These were generally used in battery hand portables.

Adrian

9th Jul 2025, 11:44 am	#1
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 15,851	Mitsubishi RF power module substitute. The flat Mitsubishi RF power modules used in a lot of 80s and 90s Japanese VHF ham transceivers are known to be prone to failure and genuine Mitsubishi ones are long since unobtainable, presumably because the stock has been used up to replace failed ones! I noticed that Moonraker and Waters&Stanton are now listing a Toshiba part, SAV7 - as a replacement for the Mitsubishi M57733. Price £25. No experience of actually doing the swap, the Mitsu block in my Trio-Kenwood TR-7800 is still working OK, but it's interesting to see that if it does die there is a suggested replacement. Note that this is a Class C amplifier and so no good for replacing the Class AB or Class B modules used in similar-era multimode transceivers. I would prefer to buy from someone like W&S than take a chance on getting a part from one of the far eastern online shops. __________________ "Anything Can Happen In The Next Half Hour!" -- Stingray (1965).

9th Jul 2025, 10:11 pm	#2
Terry_VK5TM Nonode Join Date: Oct 2010 Location: Tintinara, South Australia, Australia Posts: 2,831	Re: Mitsubishi RF power module substitute. Alternative Mitsubishi RF modules are available. RA08H1317M RF Module 8W 135-175MHz RA30H1317M1 RF Module 30W 135-175MHz RA60H1317M1A RF Module 60W 136-174MHz __________________ Terry VK5TM https://www.vk5tm.com/

12th Jul 2025, 8:27 am	#3
its ur aerial Heptode Join Date: May 2009 Location: Ryde, Isle of Wight, UK. Posts: 612	Re: Mitsubishi RF power module substitute. Thanks that's well worth knowing, Ken G6HZG. __________________ Life is not Hollywood, life is Cricklewood.

12th Jul 2025, 10:03 am	#4
AdrianH Octode Join Date: Mar 2020 Location: Blackburn with Darwen, Lancashire, UK. Posts: 1,748	Re: Mitsubishi RF power module substitute. If use to anyone to play with I have a few RA07M131M modules left over from my working days, I doubt I would get to use them now. These were generally used in battery hand portables. Adrian __________________ Asking questions and learning, or trying to! Youtube EF91Valve