|
I never liked the fact that there was the AC for the PS7 routed through the TR7. I have used a good power strip for years and tried to not switch the volume control to OFF since I read about them being unobtainable, and failing both electrically and mechanically.
?
Working on a project TR7 and PS7 with a younger ham, I decided that I should finally figure out how to keep the AC out of his and my TR7s. As we were checking out the PS7 I looked at the circuit board that has the voltage switching and all that (mounted by the switches being pop-riveted in place, seriously???) and decided there had to be a better way that to mess with that wiring.
?
And then an idea came to me that should have 40+ yrs ago when I got the rig. Surplus Sales has the Jones connectors (for a cable, but we did not connect any cable) that are the same configuration as on the back of the rig. Part Number: (CNE) P310CCT
?
With it we just jumpered pins 1-2 and 3-4 inside the connector (check your PS7 and TR7 manuals to see) and then plugged it on to the cable from the PS7 and it works just like the PS7 was plugged into a turned-on radio. If you need ALC or VOX, you'll need to get another connector to plug-in to the back of the TR7, but we have not needed either yet.
?
Then we leave the PS7 cable that has the AC and wires for the ALC and VOX coiled up behind the PS7 and turn things on with the power strip. Now only the 12V cable is plugged into the TR7. Of course the fan will need to be changed to 12 VDC on the radio. That will be our next upgrade.
?
Before recommending the Jones connector from Surplus Sales to the group, I called them to make sure there were more available. They checked stock and said that they should have at least several hundred.
?
Thought I'd share this idea with the group. I am sure others may have done something similar, but it is nice to know where we can still get Jones connectors at a reasonable price.
?
73,
-Glenn/ WB0DKT
|
That will work! I have also seen PS7s modified with an ugly toggle switch on the front panel there but that's a road I did not really want to go down. An idea I have considered is adding a small vampire circuit with a relay inside the PS7 and just run a DC control voltage to the rig, but then that does not solve the power switch wear issue. So I just use a power strip. It works well enough for me. However, if you don't like unsightly power strips hanging around here is another idea sort of related. Recently I was pondering a way to easily kill my RFI generating satellite receiver when I want to hear stuff on HF. Around the holidays I found these in the Christmas lighting supplies section of my local Home Depot. Cheap. Supposedly capable of switching 15A and it sounds like they can handle moderately inductive loads. Problem solved. Although I did have to think about what to use the other two in the three-pack for. There was nothing in the shack that I "need" to turn on and off wirelessly but I found something to use the second one for. They have been working well for several months. We'll see if they survive our thunderstorm season. Ironically, I did put the third one in the shack last week so I could remotely reboot my LAN connected SDR receiver when it drops off the network. I suppose you could use one to turn the PS7 and a FA7 on the rig on at the same time, saving having to rig up a DC fan. It would take just a short extension cord from the FA7 to the 2nd receptacle on the box. 73 -Jim NU0C On Mon, 31 Mar 2025 20:21:31 -0700 "Glenn Hetchler WB0DKT via groups.io" <ghetch@...> wrote: I never liked the fact that there was the AC for the PS7 routed through the TR7. I have used a good power strip for years and tried to not switch the volume control to OFF since I read about them being unobtainable, and failing both electrically and mechanically.
Working on a project TR7 and PS7 with a younger ham, I decided that I should finally figure out how to keep the AC out of his and my TR7s. As we were checking out the PS7 I looked at the circuit board that has the voltage switching and all that (mounted by the switches being pop-riveted in place, seriously???) and decided there had to be a better way that to mess with that wiring.
And then an idea came to me that should have 40+ yrs ago when I got the rig. Surplus Sales has the Jones connectors (for a cable, but we did not connect any cable) that are the same configuration as on the back of the rig. Part Number: (CNE) P310CCT
With it we just jumpered pins 1-2 and 3-4 inside the connector (check your PS7 and TR7 manuals to see) and then plugged it on to the cable from the PS7 and it works just like the PS7 was plugged into a turned-on radio. If you need ALC or VOX, you'll need to get another connector to plug-in to the back of the TR7, but we have not needed either yet.
Then we leave the PS7 cable that has the AC and wires for the ALC and VOX coiled up behind the PS7 and turn things on with the power strip. Now only the 12V cable is plugged into the TR7. Of course the fan will need to be changed to 12 VDC on the radio. That will be our next upgrade.
Before recommending the Jones connector from Surplus Sales to the group, I called them to make sure there were more available. They checked stock and said that they should have at least several hundred.
Thought I'd share this idea with the group. I am sure others may have done something similar, but it is nice to know where we can still get Jones connectors at a reasonable price.
73,
-Glenn/ WB0DKT
-- 73 -Jim NU0C
|
If they¡¯re built anything like the single remote plus switch, they should handle substantial loads. I have one in my woodshop that I use to turn on my 1 hp dust collector. Works like a charm.?
I don¡¯t need that in my shack, as I have a C-4¡
73,
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
On Tue, Apr 1, 2025 at 00:06, Jim Shorney via groups.io < jimNU0C@...> wrote:
That will work! I have also seen PS7s modified with an ugly toggle switch on the front panel there but that's a road I did not really want to go down. An idea I have considered is adding a small vampire circuit with a relay inside the PS7 and just run a DC control voltage to the rig, but then that does not solve the power switch wear issue. So I just use a power strip. It works well enough for me.
However, if you don't like unsightly power strips hanging around here is another idea sort of related. Recently I was pondering a way to easily kill my RFI generating satellite receiver when I want to hear stuff on HF. Around the holidays I found these in the Christmas lighting supplies section of my local Home Depot. Cheap.
https://www.homedepot.com/p/Commercial-Electric-Wireless-Indoor-Remote-Control-AC-DC-Adapter-White-3-Pack-LA-YK08/329046003
Supposedly capable of switching 15A and it sounds like they can handle moderately inductive loads. Problem solved. Although I did have to think about what to use the other two in the three-pack for. There was nothing in the shack that I "need" to turn on and off wirelessly but I found something to use the second one for. They have been working well for several months. We'll see if they survive our thunderstorm season. Ironically, I did put the third one in the shack last week so I could remotely reboot my LAN connected SDR receiver when it drops off the network. I suppose you could use one to turn the PS7 and a FA7 on the rig on at the same time, saving having to rig up a DC fan. It would take just a short extension cord from the FA7 to the 2nd receptacle on the box.
73
-Jim
NU0C
On Mon, 31 Mar 2025 20:21:31 -0700
"Glenn Hetchler WB0DKT via groups.io" <ghetch@...> wrote:
> I never liked the fact that there was the AC for the PS7 routed through the TR7. I have used a good power strip for years and tried to not switch the volume control to OFF since I read about them being unobtainable, and failing both electrically and mechanically.
>
> Working on a project TR7 and PS7 with a younger ham, I decided that I should finally figure out how to keep the AC out of his and my TR7s. As we were checking out the PS7 I looked at the circuit board that has the voltage switching and all that (mounted by the switches being pop-riveted in place, seriously???) and decided there had to be a better way that to mess with that wiring.
>
> And then an idea came to me that should have 40+ yrs ago when I got the rig. Surplus Sales has the Jones connectors (for a cable, but we did not connect any cable) that are the same configuration as on the back of the rig. Part Number: (CNE) P310CCT
> https://www.surplussales.com/items/107904/vintage-cinch-jones-metal-backshell-clamp/
>
> With it we just jumpered pins 1-2 and 3-4 inside the connector (check your PS7 and TR7 manuals to see) and then plugged it on to the cable from the PS7 and it works just like the PS7 was plugged into a turned-on radio. If you need ALC or VOX, you'll need to get another connector to plug-in to the back of the TR7, but we have not needed either yet.
>
> Then we leave the PS7 cable that has the AC and wires for the ALC and VOX coiled up behind the PS7 and turn things on with the power strip. Now only the 12V cable is plugged into the TR7. Of course the fan will need to be changed to 12 VDC on the radio. That will be our next upgrade.
>
> Before recommending the Jones connector from Surplus Sales to the group, I called them to make sure there were more available. They checked stock and said that they should have at least several hundred.
>
> Thought I'd share this idea with the group. I am sure others may have done something similar, but it is nice to know where we can still get Jones connectors at a reasonable price.
>
> 73,
> -Glenn/ WB0DKT
>
>
>
>
>
--
73
-Jim
NU0C
|
Great idea. Ordering the connector today as I hate having to drag both cables up and over the bench when I work on this, and I'm still tempting fate by using the volume control on/off. I have my whole house set up on those remote switches by Gosund so it's a simple task to add another.?
?
If anyone finds an appropriate 12V muffin fan, let me know. I was going to replace this anyway as it's turbine-like loud. Perhaps something like unit would work.?
?
It's currently blowing OUT of the unit; is this the latest best practice??
--
Craig/W8CS
Greenville, SC
|
I did this 30 years ago to my bench PS-7's.? Yes, there's still AC to the radio, but it's only the start relay coil and the fan.?
Any host radio is protected from power transformer inrush.? Both supplies still in daily use.? Jim WA9Z
?
|
On 2025-03-31 21:06, Jim Shorney via groups.io wrote: *** Or you could get a "clapper" :). - Jerry, KF6VB Supposedly capable of switching 15A and it sounds like they can handle
moderately inductive loads. Problem solved. Although I did have to
think about what to use the other two in the three-pack for. There was
nothing in the shack that I "need" to turn on and off wirelessly but I
found something to use the second one for. They have been working well
for several months. We'll see if they survive our thunderstorm season.
Ironically, I did put the third one in the shack last week so I could
remotely reboot my LAN connected SDR receiver when it drops off the
network. I suppose you could use one to turn the PS7 and a FA7 on the
rig on at the same time, saving having to rig up a DC fan. It would
take just a short extension cord from the FA7 to the 2nd receptacle on
the box.
73
-Jim
NU0C
On Mon, 31 Mar 2025 20:21:31 -0700
"Glenn Hetchler WB0DKT via groups.io" <ghetch@...> wrote:
I never liked the fact that there was the AC for the PS7 routed through the TR7. I have used a good power strip for years and tried to not switch the volume control to OFF since I read about them being unobtainable, and failing both electrically and mechanically.
Working on a project TR7 and PS7 with a younger ham, I decided that I should finally figure out how to keep the AC out of his and my TR7s. As we were checking out the PS7 I looked at the circuit board that has the voltage switching and all that (mounted by the switches being pop-riveted in place, seriously???) and decided there had to be a better way that to mess with that wiring.
And then an idea came to me that should have 40+ yrs ago when I got the rig. Surplus Sales has the Jones connectors (for a cable, but we did not connect any cable) that are the same configuration as on the back of the rig. Part Number: (CNE) P310CCT
With it we just jumpered pins 1-2 and 3-4 inside the connector (check your PS7 and TR7 manuals to see) and then plugged it on to the cable from the PS7 and it works just like the PS7 was plugged into a turned-on radio. If you need ALC or VOX, you'll need to get another connector to plug-in to the back of the TR7, but we have not needed either yet.
Then we leave the PS7 cable that has the AC and wires for the ALC and VOX coiled up behind the PS7 and turn things on with the power strip. Now only the 12V cable is plugged into the TR7. Of course the fan will need to be changed to 12 VDC on the radio. That will be our next upgrade.
Before recommending the Jones connector from Surplus Sales to the group, I called them to make sure there were more available. They checked stock and said that they should have at least several hundred.
Thought I'd share this idea with the group. I am sure others may have done something similar, but it is nice to know where we can still get Jones connectors at a reasonable price.
73,
-Glenn/ WB0DKT
--
73
-Jim
NU0C
|
Perhaps a switch that responds to commands spoken in Morse code.
Barry - N4BUQ
toggle quoted message
Show quoted text
On 2025-03-31 21:06, Jim Shorney via groups.io wrote:
*** Or you could get a "clapper" :).
- Jerry, KF6VB
Supposedly capable of switching 15A and it sounds like they can handle
moderately inductive loads. Problem solved. Although I did have to
think about what to use the other two in the three-pack for. There was
nothing in the shack that I "need" to turn on and off wirelessly but I
found something to use the second one for. They have been working well
for several months. We'll see if they survive our thunderstorm season.
Ironically, I did put the third one in the shack last week so I could
remotely reboot my LAN connected SDR receiver when it drops off the
network. I suppose you could use one to turn the PS7 and a FA7 on the
rig on at the same time, saving having to rig up a DC fan. It would
take just a short extension cord from the FA7 to the 2nd receptacle on
the box.
73
-Jim
NU0C
On Mon, 31 Mar 2025 20:21:31 -0700
"Glenn Hetchler WB0DKT via groups.io" <ghetch@...>
wrote:
I never liked the fact that there was the AC for the PS7 routed
through the TR7. I have used a good power strip for years and tried to
not switch the volume control to OFF since I read about them being
unobtainable, and failing both electrically and mechanically.
Working on a project TR7 and PS7 with a younger ham, I decided that I
should finally figure out how to keep the AC out of his and my TR7s.
As we were checking out the PS7 I looked at the circuit board that has
the voltage switching and all that (mounted by the switches being
pop-riveted in place, seriously???) and decided there had to be a
better way that to mess with that wiring.
And then an idea came to me that should have 40+ yrs ago when I got
the rig. Surplus Sales has the Jones connectors (for a cable, but we
did not connect any cable) that are the same configuration as on the
back of the rig. Part Number: (CNE) P310CCT
With it we just jumpered pins 1-2 and 3-4 inside the connector (check
your PS7 and TR7 manuals to see) and then plugged it on to the cable
from the PS7 and it works just like the PS7 was plugged into a
turned-on radio. If you need ALC or VOX, you'll need to get another
connector to plug-in to the back of the TR7, but we have not needed
either yet.
Then we leave the PS7 cable that has the AC and wires for the ALC and
VOX coiled up behind the PS7 and turn things on with the power strip.
Now only the 12V cable is plugged into the TR7. Of course the fan will
need to be changed to 12 VDC on the radio. That will be our next
upgrade.
Before recommending the Jones connector from Surplus Sales to the
group, I called them to make sure there were more available. They
checked stock and said that they should have at least several hundred.
Thought I'd share this idea with the group. I am sure others may have
done something similar, but it is nice to know where we can still get
Jones connectors at a reasonable price.
73,
-Glenn/ WB0DKT
--
73
-Jim
NU0C
|
On 2025-04-01 13:15, n4buq wrote: Perhaps a switch that responds to commands spoken in Morse code. *** I've used code for I/O on a few projects. Well, mostly for O. Once upon a time, I was working on a project at work that had a CPU that talked to another CPU. They communicated via a shared memory interface. The CPU I was working on had no I/O, except for a single reset line to the main CPU - so it could act as a watchdog. I got the program working fine on the ICE ( In Circuit Emulator ). But when I plugged in a real CPU, it sat like a lump and did nothing. I beat my head against the wall with that thing for about a week, then had an idea... I brought in a small speaker and a resistor. Hooked them to that one I/O line, and wrote a quickie morse code driver. "If you get here, send an "A", if you get there, send a "B"....etc. Had it figured out in about 15 minutes. Another one: I was doing these back exercises, each movement to be held for 5 seconds. Sure would be nice to have a box with a button that would beep after 5 seconds... Then I thought - why not have it count my repetitions? And so it does....in Morse code. A third one: Somebody posted an adventure game on Hackaday with Morse code input & output. It worked with a blinking light. I modified it so it would beep instead. Much more ham-friendly. I'm going to put it in a nice little box and take it to the local radio club meeting. - Jerry, KF6VB Barry - N4BUQ
On 2025-03-31 21:06, Jim Shorney via groups.io wrote:
*** Or you could get a "clapper" :).
- Jerry, KF6VB
Supposedly capable of switching 15A and it sounds like they can handle
moderately inductive loads. Problem solved. Although I did have to
think about what to use the other two in the three-pack for. There was
nothing in the shack that I "need" to turn on and off wirelessly but I
found something to use the second one for. They have been working well
for several months. We'll see if they survive our thunderstorm season.
Ironically, I did put the third one in the shack last week so I could
remotely reboot my LAN connected SDR receiver when it drops off the
network. I suppose you could use one to turn the PS7 and a FA7 on the
rig on at the same time, saving having to rig up a DC fan. It would
take just a short extension cord from the FA7 to the 2nd receptacle on
the box.
73
-Jim
NU0C
On Mon, 31 Mar 2025 20:21:31 -0700
"Glenn Hetchler WB0DKT via groups.io" <ghetch@...>
wrote:
I never liked the fact that there was the AC for the PS7 routed
through the TR7. I have used a good power strip for years and tried to
not switch the volume control to OFF since I read about them being
unobtainable, and failing both electrically and mechanically.
Working on a project TR7 and PS7 with a younger ham, I decided that I
should finally figure out how to keep the AC out of his and my TR7s.
As we were checking out the PS7 I looked at the circuit board that has
the voltage switching and all that (mounted by the switches being
pop-riveted in place, seriously???) and decided there had to be a
better way that to mess with that wiring.
And then an idea came to me that should have 40+ yrs ago when I got
the rig. Surplus Sales has the Jones connectors (for a cable, but we
did not connect any cable) that are the same configuration as on the
back of the rig. Part Number: (CNE) P310CCT
With it we just jumpered pins 1-2 and 3-4 inside the connector (check
your PS7 and TR7 manuals to see) and then plugged it on to the cable
from the PS7 and it works just like the PS7 was plugged into a
turned-on radio. If you need ALC or VOX, you'll need to get another
connector to plug-in to the back of the TR7, but we have not needed
either yet.
Then we leave the PS7 cable that has the AC and wires for the ALC and
VOX coiled up behind the PS7 and turn things on with the power strip.
Now only the 12V cable is plugged into the TR7. Of course the fan will
need to be changed to 12 VDC on the radio. That will be our next
upgrade.
Before recommending the Jones connector from Surplus Sales to the
group, I called them to make sure there were more available. They
checked stock and said that they should have at least several hundred.
Thought I'd share this idea with the group. I am sure others may have
done something similar, but it is nice to know where we can still get
Jones connectors at a reasonable price.
73,
-Glenn/ WB0DKT
--
73
-Jim
NU0C
|
Just a thought for a simple option but not that smart.
I have a few tube KW Electronics transceivers (in addition to Drakes).? Two were bought with an on off switch on the power supply unit, being home mods.
But the TR7 fan is an issue since I assume it would be AC only.?
Nigel
On 2025-04-01 13:15, n4buq wrote:
> Perhaps a switch that responds to commands spoken in Morse code.
*** I've used code for I/O on a few projects.? Well, mostly for O.
Once upon a time, I was working on a project at work that had a CPU that
talked to
another CPU.? They communicated via a shared memory interface.? The CPU
I was working on had no I/O, except for a single reset line to the main
CPU -
so it could act as a watchdog.? I got the program working fine on the
ICE ( In Circuit
Emulator ).? But when I plugged in a real CPU, it sat like a lump and
did nothing.
I beat my head against the wall with that thing for about a week, then
had an idea...
I brought in a small speaker and a resistor.? Hooked them to that one
I/O line, and
wrote a quickie morse code driver.? "If you get here, send an "A", if
you get there, send a "B"....etc.
Had it figured out in about 15 minutes.
Another one:? ?I was doing these back exercises, each movement to be
held for 5 seconds.? Sure would
be nice to have a box with a button that would beep after 5 seconds...
Then I thought - why not have it
count my repetitions?? And so it does....in Morse code.
A third one:? Somebody posted an adventure game on Hackaday with Morse
code input & output.? It worked
with a blinking light.? I modified it so it would beep instead.? Much
more ham-friendly.? I'm going to
put it in a nice little box and take it to the local radio club meeting.
? ? ? ? ? ? ? ? ?- Jerry, KF6VB
>
> Barry - N4BUQ
>
>> On 2025-03-31 21:06, Jim Shorney via wrote:
>>
>>>
>>>
>>
>> *** Or you could get a "clapper" :).
>>
>>
>>
>>? ? ? ? ? ? ? ? - Jerry, KF6VB
>>
>>>
>>> Supposedly capable of switching 15A and it sounds like they can
>>> handle
>>> moderately inductive loads. Problem solved. Although I did have to
>>> think about what to use the other two in the three-pack for. There
>>> was
>>> nothing in the shack that I "need" to turn on and off wirelessly but
>>> I
>>> found something to use the second one for. They have been working
>>> well
>>> for several months. We'll see if they survive our thunderstorm
>>> season.
>>> Ironically, I did put the third one in the shack last week so I could
>>> remotely reboot my LAN connected SDR receiver when it drops off the
>>> network. I suppose you could use one to turn the PS7 and a FA7 on the
>>> rig on at the same time, saving having to rig up a DC fan. It would
>>> take just a short extension cord from the FA7 to the 2nd receptacle
>>> on
>>> the box.
>>>
>>> 73
>>>
>>> -Jim
>>> NU0C
>>>
>>> On Mon, 31 Mar 2025 20:21:31 -0700
>>> "Glenn Hetchler WB0DKT via " <ghetch=[email protected]>
>>> wrote:
>>>
>>>> I never liked the fact that there was the AC for the PS7 routed
>>>> through the TR7. I have used a good power strip for years and tried
>>>> to
>>>> not switch the volume control to OFF since I read about them being
>>>> unobtainable, and failing both electrically and mechanically.
>>>>
>>>> Working on a project TR7 and PS7 with a younger ham, I decided that
>>>> I
>>>> should finally figure out how to keep the AC out of his and my TR7s.
>>>> As we were checking out the PS7 I looked at the circuit board that
>>>> has
>>>> the voltage switching and all that (mounted by the switches being
>>>> pop-riveted in place, seriously???) and decided there had to be a
>>>> better way that to mess with that wiring.
>>>>
>>>> And then an idea came to me that should have 40+ yrs ago when I got
>>>> the rig. Surplus Sales has the Jones connectors (for a cable, but we
>>>> did not connect any cable) that are the same configuration as on the
>>>> back of the rig. Part Number: (CNE) P310CCT
>>>>
>>>>
>>>> With it we just jumpered pins 1-2 and 3-4 inside the connector
>>>> (check
>>>> your PS7 and TR7 manuals to see) and then plugged it on to the cable
>>>> from the PS7 and it works just like the PS7 was plugged into a
>>>> turned-on radio. If you need ALC or VOX, you'll need to get another
>>>> connector to plug-in to the back of the TR7, but we have not needed
>>>> either yet.
>>>>
>>>> Then we leave the PS7 cable that has the AC and wires for the ALC
>>>> and
>>>> VOX coiled up behind the PS7 and turn things on with the power
>>>> strip.
>>>> Now only the 12V cable is plugged into the TR7. Of course the fan
>>>> will
>>>> need to be changed to 12 VDC on the radio. That will be our next
>>>> upgrade.
>>>>
>>>> Before recommending the Jones connector from Surplus Sales to the
>>>> group, I called them to make sure there were more available. They
>>>> checked stock and said that they should have at least several
>>>> hundred.
>>>>
>>>> Thought I'd share this idea with the group. I am sure others may
>>>> have
>>>> done something similar, but it is nice to know where we can still
>>>> get
>>>> Jones connectors at a reasonable price.
>>>>
>>>> 73,
>>>> -Glenn/ WB0DKT
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>>
>>> 73
>>>
>>> -Jim
>>> NU0C
>>>
>>>
>>>
>>
>>
>>
>
>
>
|
Glenn,
?
Mine is another vote for never looping the AC primary circuit into a transceiver.
?
I had a similar idea to you. As the PS7 has no mains on/off switch of it's own, I thought I would get hold of a chassis mount version of the relevant miniature-Jones connector and mount it on a small box. Also on the box, I would install a mains on/off switch that connected across the relevant pins of the connector. Going further I thought, that small box could easily house a resistor and another switch to make a simple, manual soft-start arrangement for the power supply. Add a fuse to protect the soft-start resistor, plus suitable indicator(s) to make it fancy, if you like!
?
Not done it yet, as those 10-pin connectors are hard to come by on this side of the pond, plus I've been powering my TR4310 and TR7 from Non-Drake supplies.
?
I have changed the fans on both transceivers to common-or-garden 12 Volt, PC types. With the full 12 (13.8) V across them, they suck a lot of air, but are quite noisy in the process. So, I added a series resistor of around 50 Ohm in their DC feed. That reduces the voltage on the fans to something like 50% of rated and seemed to give a good compromise between airflow and dBA. I obtained the 12 V feed for the fans from one of the mini-Jones on the TR rear panel. I left the wiring and original connector in place for the Drake fan, to make the mod. was fully reversible / just in case a future owner does not share my outlook.
?
(I have implemented a similar arrangement with a Heathkit HW-101 that I am restoring. Some of the matching Heath power supplies do not have a mains on/off switch on their front panels. And were those 11-pin sockets really rated to take the heater Amps and PA anode Volts that they have to put up with?!?)
?
Regards,
?
Mark.
?
|
An even simpler soft start is to add inside the PS7 a NTC inrush limiter as found in every SMPS nowdays. /g/DRAKE-RADIO/files/TR-7/PS7-Inrush.pdfOn Wed, 02 Apr 2025 03:05:50 -0700 "atlasstuff via groups.io" <g4fph@...> wrote: Going further I thought, that small box could easily house a resistor and another switch to make a simple, manual soft-start arrangement for the power supply. -- 73 -Jim NU0C
|
Mark
Yes, good solutions for the fans and keeping the mains out and a simple switch to override the soft start resistor.
Nigel
Glenn,
?
Mine is another vote for never looping the AC primary circuit into a transceiver.
?
I had a similar idea to you. As the PS7 has no mains on/off switch of it's own, I thought I would get hold of a chassis mount version of the relevant miniature-Jones connector and mount it on a small box. Also on the box, I would install a mains on/off switch that connected across the relevant pins of the connector. Going further I thought, that small box could easily house a resistor and another switch to make a simple, manual soft-start arrangement for the power supply. Add a fuse to protect the soft-start resistor, plus suitable indicator(s) to make it fancy, if you like!
?
Not done it yet, as those 10-pin connectors are hard to come by on this side of the pond, plus I've been powering my TR4310 and TR7 from Non-Drake supplies.
?
I have changed the fans on both transceivers to common-or-garden 12 Volt, PC types. With the full 12 (13.8) V across them, they suck a lot of air, but are quite noisy in the process. So, I added a series resistor of around 50 Ohm in their DC feed. That reduces the voltage on the fans to something like 50% of rated and seemed to give a good compromise between airflow and dBA. I obtained the 12 V feed for the fans from one of the mini-Jones on the TR rear panel. I left the wiring and original connector in place for the Drake fan, to make the mod. was fully reversible / just in case a future owner does not share my outlook.
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Regards,
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Mark.
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A better soft start solution: /g/DRAKE-RADIO/files/TR-7/PS7-Inrush.pdfOn Wed, 2 Apr 2025 19:01:52 +0100 "nigel patterson G3YDT via groups.io" <wnigelpatterson@...> wrote: Yes, good solutions for the fans and keeping the mains out and a simple
switch to override the soft start resistor. -- 73 -Jim NU0C
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Jim Thank you for bringing that info on the huge in-rush and the solution to my attention. Brilliant fand from Stefan, so it must be good. I did not know that this type of thermistor existed. ? With that mega transformer in the PS7, it will deliver a big punch, and a simple solution.? I have put in thermistors after the mains fuse on tube receivers (all Class A) which have the silicon rectifiers.? More important to me since I am contemplating adding a 1 farad capacitor (from a car boom audio shop but never used) to stiffen the TR7 on Transmit.? Pity it does not fit in the case.
Nigel
A better soft start solution:
/g/DRAKE-RADIO/files/TR-7/PS7-Inrush.pdf
On Wed, 2 Apr 2025 19:01:52 +0100
"nigel patterson G3YDT via " <wnigelpatterson=[email protected]> wrote:
> Yes, good solutions for the fans and keeping the mains out and a simple
> switch to override the soft start resistor.
--
73
-Jim
NU0C
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Nigel, Have you tried splitting the high and low current power rails as described by GW4ALG? The PS7 is actually very well regulated. On Thu, 3 Apr 2025 11:01:55 +0100 "nigel patterson G3YDT via groups.io" <wnigelpatterson@...> wrote: I am contemplating
adding a 1 farad capacitor (from a car boom audio shop but never used) to
stiffen the TR7 on Transmit. Pity it does not fit in the case. -- 73 -Jim NU0C
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Jim Shorney
Craig W8CS