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Reviews For: TDK R48-30K

Category: Power Supplies

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Review Summary For : TDK R48-30K
Reviews: 1MSRP: $700
Description:
Industrial grade 48V 30AMP POWER SUPPLY
Product is in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0015
WA2JJH Rating: 2007-01-27
A 48V supply for Mosfet amplifiers Time Owned: more than 12 months.
Tube linear amps are the norm for most Hams.
Solid state amps are the nee kid on the block.
They are far more expensive in terms of PEP out/dollar. They are that way for a few reasons.
1)A matched pair of MRF-154's cost around $800.
2)Many protection circuits are required, so the Mosfet amp will not fry. Some amps use CPU's for such tasks.
3)Un-popular voltage needed. 48-50V for the Mosfets. A seperate gate bias supply. 3-9VDC@3-6 amps.

For those that are going to uild thier owm Mosfet linear amplifiers, the power supply is of major concern. Many Home brew with mixed results

I was taught engineers do not work harder, we work smarter. Why not use a supply that is off industrial quality. Absolulety short circuit proof. Voltage regulation to within 1%.
The big plus with this "bad boy" are feed back loops. These can be used for much of the protection circuits.
The power supply will shut down if your parameters are violated.
1)SWR
2)excess currant draw or over temp of the expensive mosfets.
3)Simple TTL logic gates can decide what to do.
The TDK is 48-50V with a 30AMP CW draw. No ifs ands or buts. 40A peak can be set as well.

Much of design work is highly simplified. This power supply works great with 110 or 220VAC. 30-80CPS.
The power output receptical is darn right scary.
2 huge metal bars. These will handle 100 amps easy.

Two feed back loops are provided for you own protection circuits. The loops are simply logic state 1 or zero.
One example is SWR protection. Using the defacto standard of a directional coupler can be set to trip a relay, if SWR is above a 1:2.5 swr for example. The relay complets the circuit of one of the feed back loops. The 48V supply and bias can be shut off in proper order.

High MOSFET temp is a no brainer. Thermister can complete another simple relay closure, to send a logic 1 to supply to perform shutdown or increase fan speed.
Gate bias is off or out of range, a warning LED can light.

This supply STAYS cool as a cucumber at 30 amp draw. 2 over size whisper quite fans are used.

If your building a 1500W input amp using 2 MRF-154's, you might want to consider this over built but under 15lbs power supply.