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Lucent SRFU18 as 23cm PA - Printable Version

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Lucent SRFU18 as 23cm PA - VK4WDM - 24-01-2018

Hello all

I have a Lucent SRFU18 amp module that has been converted for 23cm. Anybody using one? If so, what are you using as a 24v PSU? I cannot find any info on its current draw.  I would be also interested in how you are managing the antenna changeover switching.

73

Wayne VK4WDM

RE: Lucent SRFU18 as 23cm PA - VK3ALB - 25-01-2018

Hi Wayne,

I think these are the 60W amps that VK3XPD was selling some years ago. From memory I believe they needed around 7 amps. If I guess at worst case 40% efficiency then that seems about right.

RE: Lucent SRFU18 as 23cm PA - VK4WDM - 25-01-2018

Hi Lou

Yes it was VK3XPD. I just found his call sign written inside the unit. I was guessing about 10 amps. I connected it to an old 24v PSU that from memory is 5 amps. It works OK but drags the voltage down on transmit. I will have a hunt around for a 10 amp switch mode supply. I still need to get another coaxial relay for antenna switching.

Wayne VK4WDM

RE: Lucent SRFU18 as 23cm PA - VK3AV - 25-01-2018

I have a 23cm transverter with a PA in a rack case that was built by Alan VK3XPD for David VK3RU.

Alan tested the unit before it was sold to me and in his notes state - 

Pout = 45-50w  (with 1w drive)
24V @ 9A max.

I am not sure if it is the same PA module however.

For a PSU - there is a Mean Well  for $95 at element14 
     RSP-320-24 - AC/DC Enclosed Power Supply (PSU), 1 Outputs, 321.6 W, 24 V, 13.4 A

Regards
Bernard

RE: Lucent SRFU18 as 23cm PA - VK4ADC - 25-01-2018

Wayne

I did a google search on ' SRFU18  ' and came up with a couple of links that might take you back 5 years or so...

http://www.vklogger.com/forum/viewtopic.php?f=40&t=10370

http://www.vklogger.com/forum/viewtopic.php?f=40&t=12885


Time flies !!

RE: Lucent SRFU18 as 23cm PA - VK4WDM - 26-01-2018

(25-01-2018, 05:33 PM)VK4ADC Wrote: Wayne

I did a google search on ' SRFU18  ' and came up with a couple of links that might take you back 5 years or so...

http://www.vklogger.com/forum/viewtopic.php?f=40&t=10370

http://www.vklogger.com/forum/viewtopic.php?f=40&t=12885


Time flies !!

Hi Doug

I didn't think that old stuff was preserved. It shows how long projects take to get completed around this shack and I still haven't found the other half of my brain Big Grin

Hi Bernard

Thank you for the PSU info. I have never dealt with Element 14 but I will give them a call on Monday.

73

Wayne VK4WDM

RE: Lucent SRFU18 as 23cm PA - VK2TAX - 01-02-2018

Hello Hams
i recently purchased a lucent SRFU18 from greedybay and found your posts here
i looked inside the amp and it arrears to be  rf deck with no driver (the reason for high drive power ?)
any way i plan to enclose the deck with an appropiate size power supply and relays etc.
it has a couple of rf ports on the side labeled R and F so i assume this is forward and reverse rf power monitoring?
does anyone have a schematic ? hi hi.
cheers
rob
vk2tax-vk8cq

RE: Lucent SRFU18 as 23cm PA - VK3BCU - 01-02-2018

(24-01-2018, 03:46 PM)VK4WDM Wrote: Hello all

I have a Lucent SRFU18 amp module that has been converted for 23cm. Anybody using one? If so, what are you using as a 24v PSU? I cannot find any info on its current draw.  I would be also interested in how you are managing the antenna changeover switching.

73

Wayne VK4WDM


RE: Lucent SRFU18 as 23cm PA - VK2TAX - 02-02-2018

wayne
whatever i can find in my power supply box to suit but one that i can tweek to 26 volt as i suspect that is the correct rail voltage for the amp
current wise around 6-8 amp i will check the transistor specs for Vcc to be sure
perhaps a sequencer from w6pql ? to work the relays and delay
and a what i have on hand is a pair of ducommun sealed rf relays (ex something) with mini uhf connectors
not much info otherwise on the net but ill keep searching.
ps
did you get the ft 847 working ? as i managed to get mine partially working but gave up in the end and designated it to the bin.

RE: Lucent SRFU18 as 23cm PA - VK3BCU - 02-02-2018

Hi,

the MRF 2006R in the lucent amp is a 25 volt device,
any more than 24 volts is very risky, I run mine at 24.5 volts,
Allan VK3XPD only recommends 24volts


cheers Neil

RE: Lucent SRFU18 as 23cm PA - VK4WDM - 05-02-2018

(02-02-2018, 02:51 PM)VK2TAX Wrote: wayne
whatever i can find in  my power supply box to suit but one that i can tweek to 26 volt as i suspect that is the correct rail voltage for the amp
current wise around 6-8 amp i will check the transistor specs for Vcc to be sure
perhaps a sequencer from w6pql ? to work the relays and delay
and a what i have on hand is  a pair of ducommun sealed rf relays (ex something) with mini uhf connectors
not much info otherwise on the net but ill keep searching.
ps
did you get the ft 847 working ? as i managed to get mine partially working but gave up in the end and  designated it to the bin.

I have got the relays etc for the amp. Just chasing up a PSU.  Have not tackled my FT-847 yet. Real pit about yours.

Wayne