Re: [drakelist] (no subject)

[Fernando]

Hi Randy!

There are some substantial differences between the PS7 and the PS75. Basically, PS7 will deliver 25A, and PS75 just 15A. I have pasted below the general descriptions of both, for reference.

If I was you, I would go for the PS7. If you are not completely happy with the cosmetics, I don't think restoring it should be a big problem, and it can be fun too. Check if it comes with a cooling fan, which is an interesting option to that power supply.

Hope this is useful

73

Fernando, EA4BB  

 

The PS-7 is a 13.6 volt DC regulated power supply capable of delivering up to 25 amps of continuous current. Excellent voltage regulation is provided by a silicon monolithic integrated circuit and associated circuitry. Output voltage and current are adjustable with internal controls which have been factory set, to provide 13.6 volts at up to 25 amps. Other features include short circuit and over voltage protection and programmable primary voltages.An auxiliary 13.6 VDC output is provided on the rear panel and is fused internally at 1 amp. Primary voltages of 100, 120, 200, and 240 VAC, 5O-60 Hz may be used with the PS-7 and may be quickly changed via the programming switches. For demanding duty cycles, such as extended RTTY or SSTV transmission, the model 1529 FA-7 Cooling Fan is recommended for additional cooling, especially at ambient temperatures above 25°C. When the PS-7 is subjected to a current overload or short circuit condition, the regulator circuit Will automatically shut down. The unit may be reset by momentarily switching the ON-OFF switch on the TR-7 to OFF or by removing the AC primary voltage to the PS-7. The power transformer is protected by an 8 ampere type MDL fuse on primary voltages of 100 or 120 VAC or a 4 ampere type MDL fuse on 200 or 240 VAC. Refer to Figure 1 for location on the rear panel. This fuse should be replaced with another fuse of the same type and rating. The auxiliary DC output is internally fused with a 1 amp type MDL fuse. This is located inside the unit, on the regulator P.C. board. This fuse should be replaced only with another fuse of the same type and rating.  

 

The PS-75 is a high current, 13.6 VDC power supply for use with solid state transceivers in CW or SSB modes. The supply operates from a primary voltage of 100, 120,200 or 240 VAC, 50-60 Hz (switch programmed), and provides 15 amperes continuous at an unregulated voltage of 13.6 VDC (nominal) for use with solid state power amplifiers and a 3 ampere regulated out-put for use with the remainder of the transceiver. In addition, a regulated 13.6 VDC at 1 ampere is provided for auxiliary equipment. The supply was designed primarily for SSB operation at current levels of 15 amperes average and 25 amperes peak but Will also provide reliable performance on CW at current levels of up to 25 amperes. Some CW signal quality degradation due to the increased ripple may be noticed at CW power levels which exceed 15 amperes current drain (usually about 75 watts).

 

 

 

On 9/27/05, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:

Hi,

 

 I acquired a mint TR7A. However, it did not come with a power supply. I have an opportunity to purchase a PS7 in good condition or a PS75 in mint condition. I am told that both PS will work and are equivalent in output.

 

I would appreciate any advise.

 

Thanks, Randy KC2LLV