MRF477

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cb4ever104
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MRF477

Post by cb4ever104 » 30 May 2019, 11:58

Is this 477 real ?

https://www.ebay.es/itm/202690097604

Doesn't look right to me . Saying that I'm probably wrong :)
Last edited by cb4ever104 on 31 May 2019, 10:43, edited 1 time in total.
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Re: MRF477

Post by 14CS06 » 30 May 2019, 12:15

Hello Paul

MRF477 9224

seems to be the same

Image

Image

@+
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Re: MRF477

Post by cb4ever104 » 30 May 2019, 13:02

I don't like it Claude . Aren't there normally 2 little indentations on the main body ? Also , the letters don't look right to me either .
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Paul aka "Sammy". (108) PY60 Old Paisley DX Group (RIP Rab Markie)
Ex GM0 , now EA5 .
Handle "Fortune Hunter" back in "the day"
Radios ....? Anything that says "TAIWAN R.O.C" on the back.

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Re: MRF477

Post by 4a0026aleks » 30 May 2019, 14:49

Hello dears! when I had President Jackson I accidentally burned the mrf477 transistor. I successfully replaced кт920 (Russia)

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Re: MRF477

Post by 4a0026aleks » 30 May 2019, 14:50

I had to Unscrew the black radiator and drill a hole for the nut inside .output power has not changed

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Re: MRF477

Post by 4a0026aleks » 30 May 2019, 14:52

in any case, fake transistors made in Russia does not happen....

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Re: MRF477

Post by Otter » 30 May 2019, 17:31

It looks good to me.
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Re: MRF477

Post by cb4ever104 » 30 May 2019, 18:16

Otter wrote:
30 May 2019, 17:31
It looks good to me.
Fair enough Tim . :thumbup:
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Paul aka "Sammy". (108) PY60 Old Paisley DX Group (RIP Rab Markie)
Ex GM0 , now EA5 .
Handle "Fortune Hunter" back in "the day"
Radios ....? Anything that says "TAIWAN R.O.C" on the back.

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Re: MRF477

Post by Mitch » 31 May 2019, 08:46

cb4ever104 wrote:
30 May 2019, 11:58
Is this 477 real ?

https://www.ebay.es/itm/202690097604

Don't look right to me . Saying that I'm probably wrong :)
Have the pins been tinned? Back in the day we called these 'gold leggers' because the pins were gold coloured. They were expensive then too.
The perfect face for radio.

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Re: MRF477

Post by Otter » 31 May 2019, 09:08

The 1990s ones didn't have gold legs. They did in the '80s.
"To this day the words Stirling bridge conjour pride in every Scotsman's heart, while to an Englishman those same words conjour literally no feelings at all." - Cunk on Britain S1 E1
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Re: MRF477

Post by dt307 » 31 May 2019, 09:35

finished this 1 off last night with a sd1446 but a mrf455 also work the same and cheaper and will last longer than a 477 less than £30 new from a main uk dealer via rm italy.

just a thought for you sammy, i know you can make a pcb up to hold the 455/1446 but i fitted a nos driver and used final and this way the bill to the customer fitted is going to be £25.

2x560pf caps removed,bias diode removed,new 4001 bias doide fitted so not hard to do
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Re: MRF477

Post by dt307 » 31 May 2019, 09:42

side note incase any1 tries it.
you must ground 1 of the emitter tabs via 1 of the screws.
the mod is rogerbirds.....( lincoln guru) detials on the cbtricks website under hr2510
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Re: MRF477

Post by Otter » 31 May 2019, 13:03

All of these were bought before Chinese fakes were even thought of.
MRF477s.jpg
The modern fakes on eBay have the word "ON" in a circle. On semiconductors never made MRF477 or MRF497.
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"To this day the words Stirling bridge conjour pride in every Scotsman's heart, while to an Englishman those same words conjour literally no feelings at all." - Cunk on Britain S1 E1
Gorgon Brown - a man with all the joie de vivre of a haunted cave in Poland. S1 E3

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Re: MRF477

Post by cb4ever104 » 31 May 2019, 13:45

Otter wrote:
31 May 2019, 13:03
All of these were bought before Chinese fakes were even thought of.
MRF477s.jpg
The modern fakes on eBay have the word "ON" in a circle. On semiconductors never made MRF477 or MRF497.
It's strange how the sight of a few transistors can get the juices flowing :)
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Paul aka "Sammy". (108) PY60 Old Paisley DX Group (RIP Rab Markie)
Ex GM0 , now EA5 .
Handle "Fortune Hunter" back in "the day"
Radios ....? Anything that says "TAIWAN R.O.C" on the back.

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Re: MRF477

Post by Techquest » 31 May 2019, 14:01

Any so called MRF477 with a date code later than 95 is fake they stopped making them in 95.
real 477s the plastic is black not slate or gray the one in the pic is the real deal to look for anything that has any other logo than the Motorola circled M is not.
Re ON Semi as Otter said they never made 477s or 455s in fact they dont make any RF transistors for the HF bands.
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