Topics

Power Supply for FDM-S3


Ralph Brandi
 

I read the manual yesterday, and that was enough to convince me to pull
the trigger on a pre-order.  Looks to me like the performance at HF is
equivalent to the FDM-S2, and well-improved at VHF.

So now I need to get a power supply.  I've been looking for a few days,
but haven't really dealt with a radio that needed an external supply
like this.  There are relatively inexpensive linear power supplies on
eBay designed for audiophile applications, and then there are the
ham-related supplies I see at some of the radio dealers online.  Does
anyone have any suggestions on this topic?  What are other people using
for power supplies?  Elad doesn't seem to have said anything on this
other than "needs power supply, not included".


Klaus Brosche
 

What kind of advice are you asking for, I'm uncertain:

* for an ELAD radio
or
*for a power supply?

Klaus, DK3QN

Am 02.10.2020 um 22:02 schrieb Ralph Brandi:

I read the manual yesterday, and that was enough to convince me to pull
the trigger on a pre-order.  Looks to me like the performance at HF is
equivalent to the FDM-S2, and well-improved at VHF.

So now I need to get a power supply.  I've been looking for a few days,
but haven't really dealt with a radio that needed an external supply
like this.  There are relatively inexpensive linear power supplies on
eBay designed for audiophile applications, and then there are the
ham-related supplies I see at some of the radio dealers online.  Does
anyone have any suggestions on this topic?  What are other people using
for power supplies?  Elad doesn't seem to have said anything on this
other than "needs power supply, not included".



Richard Langley
 

I interpret the request as for a good power supply. It would be a good idea if ELAD USA were to offer a good linear power supply in their available products list.

-- Richard Langley

-----------------------------------------------------------------------------
| Richard B. Langley E-mail: lang@unb.ca |
| Geodetic Research Laboratory Web: http://gge.unb.ca |
| Dept. of Geodesy and Geomatics Engineering Phone: +1 506 453-5142 |
| University of New Brunswick |
| Fredericton, N.B., Canada E3B 5A3 |
| Fredericton? Where's that? See: http://www.fredericton.ca/ |
-----------------------------------------------------------------------------




________________________________________
From: EladSDR@groups.io <EladSDR@groups.io> on behalf of Klaus Brosche via groups.io <klaus.brosche=mail.de@groups.io>
Sent: October 2, 2020 5:23 PM
To: EladSDR@groups.io
Subject: Re: [EladSDR] Power Supply for FDM-S3

🎃CAUTION: This email comes from outside of UNB. Do not open any links or attachments unless you recognize the sender and know the content is safe.
What kind of advice are you asking for, I'm uncertain:

* for an ELAD radio
or
*for a power supply?

Klaus, DK3QN

Am 02.10.2020 um 22:02 schrieb Ralph Brandi:
I read the manual yesterday, and that was enough to convince me to pull
the trigger on a pre-order. Looks to me like the performance at HF is
equivalent to the FDM-S2, and well-improved at VHF.

So now I need to get a power supply. I've been looking for a few days,
but haven't really dealt with a radio that needed an external supply
like this. There are relatively inexpensive linear power supplies on
eBay designed for audiophile applications, and then there are the
ham-related supplies I see at some of the radio dealers online. Does
anyone have any suggestions on this topic? What are other people using
for power supplies? Elad doesn't seem to have said anything on this
other than "needs power supply, not included".


Ralph Brandi
 

Klaus Brosche wrote:
What kind of advice are you asking for, I'm uncertain:
* for an ELAD radio
or
*for a power supply?
As the Subject says, I'm looking for suggestions on power supplies. I already ordered the radio, don't need any advice on that. :-)


Ron Hunsicker
 

Ralph,


Since the base S3 is said to draw 0.7 amp and the OCXO model 1.1 amp, that's quite the wall wart!  To be safe, 1.5 or 2 amps?

Consider instead a Pyramid PS4KX; about $40, delivered, from Amazon.  3A @ 13.8 volts continuous from a linear supply.  I have one and run a Wellbrook, a DXEngineering Amplified Vertical, and an Elad ASA-42 with it and the voltage is steady at 13.8V.  The total load is about an amp.  It's been a happy power supply for about three years.  Running 24/7/365, it is slightly warmer than my hand.  Two binding posts on the front panel (my only bitch), an on-off switch, and no gauges, but it does the job.

Since I ordered the OCXO model, I will still have about an amp in reserve, so I am comfy.


Stay safe,

Ron


--
Ron Hunsicker
1238 Cleveland Avenue
Wyomissing, PA 19610-2102
610-478-0371
ronhunsi at ptd dot net


"Democracy dies in darkness"


g0ofe
 

I'd just get a small 13.8v linear power supply, perhaps 3A or so.

Something like this https://www.nevadaradio.co.uk/product/nevada-psw-04/

On 02/10/2020 20:39, Ralph Brandi wrote:
Klaus Brosche wrote:
> What kind of advice are you asking for, I'm uncertain:

> * for an ELAD radio
> or
> *for a power supply?

As the Subject says, I'm looking for suggestions on power supplies. I already ordered the radio, don't need any advice on that. :-)







Simon
 

May i put my penny worth in..

NO NOT a pyramid ps4kx. Or similar cb psu.

Specs say nothing about over voltage protection, just overload.

So if the pass transistor goes short circuit it will put max un regulated volts out..ie 17-20+v

Bye bye expensive s3.. not warranty claim..no elad fixing for free..

Buy a proper one with all protection crts..go speak to your local ham store.. costs more but ??

Do not but smpsu type..risk of noise..( whatever they say.)

Mine is home made..fully protected..but i have no desires to lose my ham gear due to a $2 transistor giving up the ghost..

Simon g0zen


Klaus Brosche
 

Exactly that:

a LINEAR PSU, 4+ to 8 amps, not a 'switching type' PSU.

Linear PSUs, if designed appropriately, have much less RF noise
on the DC line compared to average Switch Mode PSUs.

At this low current consumption, I'd suggest an adder Ampere-wise
of 2x to 3x (my choice) of what is needed by the unit attached.

These linear PSUs have much higher thermal dissipation rates
compared to Switch Mode PSUs.

The thermal dissipation occurs mainly at the pass transistors,
mounted to a heat sink.

Quite often, the thermal dissipation capabilities of the heatsink
are not designed for max. spec'd current of the linear PSU for
extended useage (continuous hours of operation).

Thus this 'safety' factor.

In case a pass transistor fails (short between Collector and
Emitter), e.g. due to thermal stress, the full voltage of the rectifier
will be present at the PSU output, which in case of a 12 volt PSU
will be around 18 to 20+ volts.

Which will quite likely fry your connected radio!

Klaus, DK3QN









Am 02.10.2020 um 23:00 schrieb g0ofe:

I'd just get a small 13.8v linear power supply, perhaps 3A or so.

Something like this https://www.nevadaradio.co.uk/product/nevada-psw-04/

On 02/10/2020 20:39, Ralph Brandi wrote:
Klaus Brosche wrote:
> What kind of advice are you asking for, I'm uncertain:

> * for an ELAD radio
> or
> *for a power supply?

As the Subject says, I'm looking for suggestions on power supplies. I already ordered the radio, don't need any advice on that. :-)








Paul Jones
 

I run mine off my Yaesu FP1030 that I use in my shack, and for shows like Dayton we used MFJ 3-5amp supplies. 

Paul EladUSA 




On Oct 2, 2020, at 17:25, Klaus Brosche <klaus.brosche@...> wrote:


Exactly that:

a LINEAR PSU, 4+ to 8 amps, not a 'switching type' PSU.

Linear PSUs, if designed appropriately, have much less RF noise
on the DC line compared to average Switch Mode PSUs.

At this low current consumption, I'd suggest an adder Ampere-wise
of 2x to 3x (my choice) of what is needed by the unit attached.

These linear PSUs have much higher thermal dissipation rates
compared to Switch Mode PSUs.

The thermal dissipation occurs mainly at the pass transistors,
mounted to a heat sink.

Quite often, the thermal dissipation capabilities of the heatsink
are not designed for max. spec'd current of the linear PSU for
extended useage (continuous hours of operation).

Thus this 'safety' factor.

In case a pass transistor fails (short between Collector and
Emitter), e.g. due to thermal stress, the full voltage of the rectifier
will be present at the PSU output, which in case of a 12 volt PSU
will be around 18 to 20+ volts.

Which will quite likely fry your connected radio!

Klaus, DK3QN









Am 02.10.2020 um 23:00 schrieb g0ofe:

I'd just get a small 13.8v linear power supply, perhaps 3A or so.

Something like this https://www.nevadaradio.co.uk/product/nevada-psw-04/

On 02/10/2020 20:39, Ralph Brandi wrote:
Klaus Brosche wrote:
> What kind of advice are you asking for, I'm uncertain:

> * for an ELAD radio
> or
> *for a power supply?

As the Subject says, I'm looking for suggestions on power supplies. I already ordered the radio, don't need any advice on that. :-)








Ralph Brandi
 

Simon wrote:

NO NOT a pyramid ps4kx. Or similar cb psu.
Specs say nothing about over voltage protection, just overload.
Buy a proper one with all protection crts..go speak to your local
ham store.. costs more but ??
Okay, that makes sense (but who has a local ham store these days?

Astron appears to be the predominant supplier of linear power supplies at the online ham stores here in the US (hamradio.com, universal-radio.com). Reading their site, they mention that all but their cheapest supplies have "crowbar over voltage protection". Is that the sort of thing you're referring to?

Klaus wrote:

a LINEAR PSU, 4+ to 8 amps, not a 'switching type' PSU.
At this low current consumption, I'd suggest an adder Ampere-wise
of 2x to 3x (my choice) of what is needed by the unit attached.
That makes sense to me. Again, looking at the Astron supplies, they have a 7 amp supply that has the aforementioned crowbar protection that goes for a reasonable price, the RS-7A.


Ron Hunsicker
 

All,

Thanks for the warning. 

I've retired the Pyramid (but it fit on my desk so nicely) and replaced with with an Astron RS-12A that has a much larger footprint.  It took a bit of rearranging, but now I've got over-voltage protection for my S3 when it arrives.


Again, thanks,

Ron


--
Ron Hunsicker
1238 Cleveland Avenue
Wyomissing, PA 19610-2102
610-478-0371
ronhunsi at ptd dot net


"Democracy dies in darkness"


Simon
 

Good to hear!

And yes crow bar over voltage protection is ok. Not the best way of doing it, but ok and generally good enough.


Klaus Brosche
 

BTW,
You can add an over voltage protection circuitry to (almost) any PSU via a separate box
interfaced between the voltage output terminals of the PSU and and the voltage input
terminals of your device to be powered.

The 'brutal' method (a thyristor, zener diode, some resistors and caps), aka 'crow bar',
blows a fuse at the input side of that crow bar box/circuitry, if the supplied voltage
is equal or higher than what the circuit components are set for.

A way more gentle method for over voltage protection was published e.g. in
QST magazine May 2017 pp 32 to 34.
This can also be used as an iterfaced box between any PSU (circa 13 V DC +/-
a few volts) and the device to be powered.
This circuitry protects from over voltage *and* from reverse polarity, at the circuit
input side, that is! It uses 2 low RDS-on (about 4 milli-Ohms) power MOSFETS in
order to provide these 2 tasks.

It needs to be noted that this circuitry was intended for about 20 Amps peak
supplied to a 100 watts transceiver.

In case that much less current (e.g. 5 Amps or so) needs to be handled, MOSFETs
of lower dissipation handling specs and higher RDS-on may be used, of course.

However, this circuitry is a bit more complicated to be physically
implemented as it uses a tiny SMD LTC4365 IC, which is a 8-pin SOT-23 chip
with 0.65 cm (0.026 inches) pin to pin separation.
For further information please see the QST article.

73, Klaus, DK3QN


Am 03.10.2020 um 02:54 schrieb Simon:

Good to hear!

And yes crow bar over voltage protection is ok. Not the best way of doing it, but ok and generally good enough.



Francesco Di Giovanni
 

Hi everyone,
my S3 with OCXO, GNSS antenna, and a bandwidth of 12 MHz draws 580mA @13.8V from the power supply.
Consider eventually the optional down converter.
I am using a Riden RD6006 60V-6A switching mode power supply with no evidence at the moment of RF spurs from the power supply.
I will connect a Philips lab power supply to see if it performs better than the Riden.
There is a youtube review by EEV Blog of this power supply.

73, Francesco, IN3XZP


Simon
 

If the ryden voltage is variable from that knob then possible recipe for disaster..

Opps wife/ cat/child/ me knocked it up to 60v...= no more s3.

Variable voltage psu’s are really for experiment use only.

Be careful!!


Francesco Di Giovanni
 

Hi Simon,
there is a lock key :-)

73, Francesco, IN3XZP


Andy G4JNT
 

A true story :
This appeared in RadCom   July 2012 (hence the narrow column )

CARNAGE! Fred Zappa, 2E9ZAP [1] made
a big mistake. For convenience, “because
it was to hand”, he used an old 2A, 0 – 50V
bench-type adjustable power supply set at
12V to power his masthead mounted 24GHz
transverter. Everything worked well enough
for a long time until a recent thunderstorm.
He writes, “… [there was] a blinding big
flash and a mighty bang and a crack /fizz
which sounded like it came from my mains
sockets, although that might have been the
electric field collapsing after the strike. The
neighbour had his cordless phone go down
plus an external TV camera. I did first wonder
if it had struck my mast and his ensuing damage
was the strike dissipating through his ground.
There was no evidence of any damage to
the mast at all, so must have been a nearby
ground strike...
“I got the mast down and found the
remains of my 24GHz system following
the lightning (see Photos 1 to 3). It looks
like all the three-terminal regulators have
gone, leaving some rather messy remains
to clear up. I just hope they blew to open
circuit and saved what was downstream.
Looks like the scenario has been that the
shack 12V PSU serving the 24G may have
been hit by either a mains spike or discharge
down its mast lead on the LV side, leading
its output to soar to 50V or more when
regulation failed. This in turn took out the
three-terminal regulators. Awful smell too!”
The PSU was an old design with several
pass transistors in parallel. The induced
transient caused one to fail short circuit
and allowed the full rectified input at more
than 50V to get to the load. It is not known
whether the transient arrived on the mains
input cable or on the DC lead going up the
mast, or even as a kilovolt spike across both.
Whatever happened, it was enough to
damage the PSU and cause one device
to fail short circuit – with the knock-on
consequences. Fred continues, “… the
output fuse also blew but it seems to have
perhaps taken some time. I did smell burning
at the time but the PSU has no ON light so I
didn't realise it was off until some minutes
later, by which time the damage had been
done.”
LESSONS LEARNT. The lighting strike itself
only appears to have caused minor damage
to the PSU, causing a single pass transistor to
go short circuit. But the ensuing overvoltage
destroyed all the voltage regulators further
down the chain. Both LM317 and 78xx
types are rated for inputs up to about 30V,
so the 50V killed them. It is fortunate
that in some cases these must have then
failed open circuit, protecting more delicate
circuitry further down the chain. In other
cases it appears that tantalum capacitors
may have worked as voltage clamps,
preventing voltage levels rising too high,
although blowing themselves apart in
the process. It does appear as if some the
more sensitive and expensive and exotic
microwave semiconductors have survived,
although several were damaged or degraded
in performance. Most damage was to the
power supply regulators and decoupling
capacitors.
So what has been learnt? Firstly, for
semi-permanent installations, never use
an adjustable PSU that can ever deliver a
voltage significantly above the maximum
input allowed for any downstream equipment.
This includes all equipment with its own
power supply regulators. Even if it never
gets damaged, there may come a point
when the voltage setting control is tweaked
accidentally. Provide an overvoltage clamp
or trip on all PSUs and set this at a safe
maximum, just above the working voltage.
Do not rely on output fuses to protect
downstream equipment; the PSU mentioned
could easily supply 50V at 2A forever when
fully working. If equipment is to be left on
continuously, add extra circuitry
to kill the mains input if the output
goes under or over voltage – this is
a commonsense safety precaution
against any nasties and is best
implemented with a latching relay
system on the PSU mains input.
And do include LEDs on the PSU
to indicate input and output volts
are present and correct!
When masthead equipment is in use,
provide transient suppression components
such as Transorbs and firmly bond all
grounding cables and 0V points together.
That way, if transients do get induced,
everything ‘jumps’ together. And finally,
if you smell burning – switch off! [2].

WEBSEARCH
[1] Name and callsign have been changed to
protect the innocent and avoid embarrassment.
[2] If you smell burning switch off, but do try not
to black out half a city! See www.g4jnt.com/
Hams_Hall_Investigation_Report.pdf




On Sat, 3 Oct 2020 at 17:40, Simon <ohhellnotagain@...> wrote:
If the ryden voltage is variable from that knob then possible recipe for disaster..

Opps wife/ cat/child/ me knocked it up to 60v...= no more s3.

Variable voltage psu’s are really for experiment use only.

Be careful!!





Klaus Brosche
 

Hi Andy,

I don't think that this accident was a 'direct' hit.

I direct hit would most likely crack parts of your walls (if stone)
plus some more nasty and costly appearances.

Re. adjustable (in voltage) power supplies, especially if they can
be adjusted much above 13 volts, and no matter if they are of linear
or switched mode types:

That voltage adjustment potentiometer is highly critical, depending
on the circuitry and how this potentiometer is connected to the
circuitry.

If there is a bad contact/ contacting problem in that potentiometer,
the output voltage may get 'mad', especially if you turn this thing!

I have one of these switch mode PSUs from the Starkville company
and you may guess what happened to me!

Cure: if mechanically/space feasable, replace that simple potentiometer
with a quality multi-turn one.

Klaus, DK3QN


Am 03.10.2020 um 19:29 schrieb Andy G4JNT:

A true story :
This appeared in RadCom   July 2012 (hence the narrow column )

CARNAGE! Fred Zappa, 2E9ZAP [1] made
a big mistake. For convenience, “because
it was to hand”, he used an old 2A, 0 – 50V
bench-type adjustable power supply set at
12V to power his masthead mounted 24GHz
transverter. Everything worked well enough
for a long time until a recent thunderstorm.
He writes, “… [there was] a blinding big
flash and a mighty bang and a crack /fizz
which sounded like it came from my mains
sockets, although that might have been the
electric field collapsing after the strike. The
neighbour had his cordless phone go down
plus an external TV camera. I did first wonder
if it had struck my mast and his ensuing damage
was the strike dissipating through his ground.
There was no evidence of any damage to
the mast at all, so must have been a nearby
ground strike...
“I got the mast down and found the
remains of my 24GHz system following
the lightning (see Photos 1 to 3). It looks
like all the three-terminal regulators have
gone, leaving some rather messy remains
to clear up. I just hope they blew to open
circuit and saved what was downstream.
Looks like the scenario has been that the
shack 12V PSU serving the 24G may have
been hit by either a mains spike or discharge
down its mast lead on the LV side, leading
its output to soar to 50V or more when
regulation failed. This in turn took out the
three-terminal regulators. Awful smell too!”
The PSU was an old design with several
pass transistors in parallel. The induced
transient caused one to fail short circuit
and allowed the full rectified input at more
than 50V to get to the load. It is not known
whether the transient arrived on the mains
input cable or on the DC lead going up the
mast, or even as a kilovolt spike across both.
Whatever happened, it was enough to
damage the PSU and cause one device
to fail short circuit – with the knock-on
consequences. Fred continues, “… the
output fuse also blew but it seems to have
perhaps taken some time. I did smell burning
at the time but the PSU has no ON light so I
didn't realise it was off until some minutes
later, by which time the damage had been
done.”
LESSONS LEARNT. The lighting strike itself
only appears to have caused minor damage
to the PSU, causing a single pass transistor to
go short circuit. But the ensuing overvoltage
destroyed all the voltage regulators further
down the chain. Both LM317 and 78xx
types are rated for inputs up to about 30V,
so the 50V killed them. It is fortunate
that in some cases these must have then
failed open circuit, protecting more delicate
circuitry further down the chain. In other
cases it appears that tantalum capacitors
may have worked as voltage clamps,
preventing voltage levels rising too high,
although blowing themselves apart in
the process. It does appear as if some the
more sensitive and expensive and exotic
microwave semiconductors have survived,
although several were damaged or degraded
in performance. Most damage was to the
power supply regulators and decoupling
capacitors.
So what has been learnt? Firstly, for
semi-permanent installations, never use
an adjustable PSU that can ever deliver a
voltage significantly above the maximum
input allowed for any downstream equipment.
This includes all equipment with its own
power supply regulators. Even if it never
gets damaged, there may come a point
when the voltage setting control is tweaked
accidentally. Provide an overvoltage clamp
or trip on all PSUs and set this at a safe
maximum, just above the working voltage.
Do not rely on output fuses to protect
downstream equipment; the PSU mentioned
could easily supply 50V at 2A forever when
fully working. If equipment is to be left on
continuously, add extra circuitry
to kill the mains input if the output
goes under or over voltage – this is
a commonsense safety precaution
against any nasties and is best
implemented with a latching relay
system on the PSU mains input.
And do include LEDs on the PSU
to indicate input and output volts
are present and correct!
When masthead equipment is in use,
provide transient suppression components
such as Transorbs and firmly bond all
grounding cables and 0V points together.
That way, if transients do get induced,
everything ‘jumps’ together. And finally,
if you smell burning – switch off! [2].

WEBSEARCH
[1] Name and callsign have been changed to
protect the innocent and avoid embarrassment.
[2] If you smell burning switch off, but do try not
to black out half a city! See www.g4jnt.com/
Hams_Hall_Investigation_Report.pdf




On Sat, 3 Oct 2020 at 17:40, Simon <ohhellnotagain@...> wrote:
If the ryden voltage is variable from that knob then possible recipe for disaster..

Opps wife/ cat/child/ me knocked it up to 60v...= no more s3.

Variable voltage psu’s are really for experiment use only.

Be careful!!