MS1051 vs 2sc2879

[mr_fx]

I was looking at the data sheets and they look close... I have 4 dead ms1051 pills sitting here, and I have 4 used 2sc2879, I was thinking they might make for a decent swap without having to change much (IF ANYTHING AT ALL)

MS1051 http://www2.microsemi.com/datasheets/MS1051 datasheet Rev B.pdf

2sc2879 http://www.datasheetcatalog.org/datasheet/toshiba/1468.pdf

 

[4z4rb]

Yes it can be done.
set bias to 300mA per device and you are good!

 

[4z4rb]

Since the devices are very much alike there is no need to mod any of the transformers.
3:1 at in and 4to 1 at out will give best results.cap across trafo is 470pF-800pF max
4z4rb

 

[mr_fx]

this is on an RM Italy kl-500 rev 5.01

 

[4z4rb]

I know that amp.it is a nice box

 

[mr_fx]

I know that amp.it is a nice box

so I guess all I really need to do is replace that resistor we talked about and slap the pill is, then check the bias and set it accordingly

 

[4z4rb]

yes
i think it is 100ohm 5W metal film do not put a wirewound resistor!!
WW resistors at 27MHz are like coils.

 

[4z4rb]

look here for mods to your box

http://www.radiomanual.eu/schemi/ACC_PA/RMitaly_KL-500_mod_DG2IAQ.pdf
it is a very good file