Re: R-4C Frying Egg/Static Noise
A bad/leaky power supply filter cap could be the culprit, especially in the +14v line. Is it there with no antenna connected? How about with volume at zero?
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On 3/20/2024 4:16 PM, Ed G wrote: Folks,
???? I have a lot of the frying egg/static noise in my R-4C. I am using the Sherwood third mixer mod so don't have the usual suspect third mixer tube.? What else could be the source of that noise?
--Ed, N3CW--
--
73 de Mike, W1NR
THAT was the equation. EXISTENCE!... SURVIVAL... must cancel out... programming!
- Ruk -
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Re: R-4C Frying Egg/Static Noise
I had a noisy V4, 6BA6, IF Amplifier.
Bob K9JU
On Wednesday, March 20, 2024 at 04:16:56 PM EDT, Ed G <ed.n3cw@...> wrote:
Folks,
???? I have a lot of the frying egg/static noise in my R-4C. I am using the Sherwood third mixer mod so don't have the usual suspect third mixer tube.? What else could be the source of that noise?
--Ed, N3CW--
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R-4C Frying Egg/Static Noise
Folks,
???? I have a lot of the frying egg/static noise in my R-4C. I am using the Sherwood third mixer mod so don't have the usual suspect third mixer tube.? What else could be the source of that noise?
--Ed, N3CW--
|
Re: Another TR7 Journey begins
I finally had a chance to use a decent frequency counter today. The 40 MHz oscillator is now spot on 40 MHZ and the VCXO is right on 53.695 MHz.? But the 8.05 MHz oscillator still will not quite get to 5.645 Mhz.? The closest I can get is 5.644534 MHz with C1030 nearly all the way in.? Is that "close enough"?? The answer is probably no but can't hurt to ask, right???
73, Bill NZ0T
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TR7 - DR7 Display question
Hi All,?
I'm trying to repair a DR7 board and I would like to "turn on" all LED segments.
From the diagram, I believe that grounding pin 8 of U9032 might do it. As I don't want to ruin anything on the card, please let me know your thoughts. Thanks.
73 de Raoul? CE3RY
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Well, this is vexing,
The Drake AGC circuit is very high impedance: on the order of megohms.? It is employed to control the gain of the various stages by changing the bias voltage.
It has been awhile, so please excuse me if this is repetitive, but what is the bias voltage at TP2?
Steve Wedge, W1ES/4
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Wednesday, March 20th, 2024 at 3:06 PM, Michael Jensen <kavigal@...> wrote:
Okay quick info on progress on the saga... Replaced V4&V5 with 2 NOS tubes, that brought the meter down from ~5-6 S units to ~4 S units, still the zero pot needs to be maxed/minimize depending how we look at it. Replaced V3 as well since I got hold of an 12BE6, made no differens. I totally forgot I had several 12au6's / EF94 in stock, changed V2, just for the fun of it, made no change as expected though.
So, back to the drawing board.
Cheers..
On Sat, Mar 9, 2024 at 9:05?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Crackling sounds that affect the AGC (and thus cause the meter to deflect) are worthy of investigation. You may have a component that is either cracking (resistor) or has some intermittent dialectric issues (capacitor).
I have been promising myself that I would look into creating one of those "Mr. Carlson Super Probes". "Mr. Carlson's Lab" is on YouTube and he created an AC probe that can sniff out problems like internally arcing components. The probe is similar in concept to the old signal tracers but it is much more sensitive. I believe he has two versions: one with through-hole and the other using SMT. He demonstrated the probe on an old receiver that was showing "crackling" noises. and was able to find the bad cap within a few minutes.
Anyway, I scored another victory today: I figured out how to add a 3rd monitor to the shack computer! More screen area -- yay!
73,
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
Sent with secure email.
On Saturday, March 9th, 2024 at 1:14 PM, Michael Jensen < kavigal@...> wrote:
Well sorry for the slow reply, work just tend to take up too much of one's spare time ;). Sounds like a very nice trip you and XYL is planning, now I do not travel much these days(I used to), now I just mainly work from home and enjoy monitoring the HF bands, when 'Teams' decides to leave me alone ;).
About that Beer.. Guess I already owe you one, at least as an excuse to get myself one.
Been a few years since I was in Copenhagen, I live in the opposite end of the country all the way up to the North about 50KM south of the most northern point..
And yes we will get to the bottom of this issue, actually I notice something, when I turn on the radio 'ON' to "standby" position the meters consequential "jumps" from ~S9+20 to the S9+40 meter mark, first time I noticed I just though "ohh meter is sticky" but then while troubleshooting I fiddled with the RF gain and guess what? No "sticky" meter when RF gain is fully cranked up quickly.
I noticed twice when "cold" starting the rig, and coinciding "crackling" sound when the meter "jumped", not sure what the right term is in English / U.S.A'ish but same sound a hot 6146B tube can produce just not so pronounced.
It may not be related, just noticed it.. So.. status quo, really eager to get that 12be6 swapped, but the mail man is apparently on vacation in Hawaii current time.
/Michael.
On Thu, Mar 7, 2024 at 6:48?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Yeah, that's a shame that we still have such impediments. In the grand scheme of things, a few 60 year old tubes are nothing. If I was going to Demark this year, I'd pop a couple in my bag and trade them for a beer but we will not be in the area. We will be in HB9, DL, OE, OK, F, G, GW, GM and TF this summer. My XYL is not a ham, so I'm not bringing any radios, unfortunately :-) I mention this in case you're in any of these areas in June or July.
In a couple years, perhaps, we will get to Scandinavia. I worked in Copenhagen for a week long ago and have wanted to tour that area.
We will get to the bottom of this.
73,
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
Sent with secure email.
On Thursday, March 7th, 2024 at 12:26 PM, Michael Jensen < kavigal@...> wrote:
Steve, I'd love the approach of shotgunning, but nope I do not have a complete set.
I do have 2x12ba6 in the mail and 1 12be6 also in the mail, so that will be the starting point.
I did consider and I'd love to get a complete set from K5SVC, but it would add more than 4 times
the money I have in the R4B already, getting tubes from the US to Europe is .. insane..
So thank you to the Danish Government ;)
Anyways, will try the three tube change first, that's kinda where I'm at now.
/Michael
On Thu, Mar 7, 2024 at 5:33?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Now is the time, if you either have a spare set or have another R-4B, to swap every tube out at the same time (¡°shotgunning¡±).
I had an R-4B that was vexing me to no end until I replaced all the tubes and then put swapped the old ones back, one at a time. I found two bad/gassy 12BA6¡¯s and a 12BE6 that passed the tube tester but was no good.
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
On Thu, Mar 7, 2024 at 09:29, Michael Jensen < kavigal@...> wrote: When unpowered, S1+a hair, so very close to zero.
Have checked the following resistors so fare... Just FYI, nothing more.. R9 1.5K** Board 9 OK
R8 220K** Chassis Right Side -R OK
R12 1.5k**Board 9 OK
R13 1.5K**Board 9 OK
R16 1.5K**Board 7 OK
R17 12K* OK
R24 18K* OK
R136 1k** Chassis Left Side -R OK
R142 4.7K**Board 3 OK
R146 22K** Board 3 -- coil OK
/Michael.
On Thu, Mar 7, 2024 at 3:19?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Yes, I have been bit by one of the meter terminals. It hurts :-). This circuit is at around 150V potential.
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
On Thu, Mar 7, 2024 at 01:23, Glenn, OZ1HFT < glenn.mh.dk@...> wrote: Hi Michael
More safety: Let the Drake unlugged power plug and cable be visible to you, on your workbench, while you work on the Drake.
(Then it be much harder to get an accidently electric shock.)
--
best regards,
Glenn, OZ1HFT
|
Okay quick info on progress on the saga... Replaced V4&V5 with 2 NOS tubes, that brought the meter down from ~5-6 S units to ~4 S units, still the zero pot needs to be maxed/minimize depending how we look at it. Replaced V3 as well since I got hold of an 12BE6, made no differens. I totally forgot I had several 12au6's / EF94 in stock, changed V2, just for the fun of it, made no change as expected though.
So, back to the drawing board.
Cheers..
?
On Sat, Mar 9, 2024 at 9:05?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Crackling sounds that affect the AGC (and thus cause the meter to deflect) are worthy of investigation.? You may have a component that is either cracking (resistor) or has some intermittent dialectric issues (capacitor).
I have been promising myself that I would look into creating one of those "Mr. Carlson Super Probes".? "Mr. Carlson's Lab" is on YouTube and he created an AC probe that can sniff out problems like internally arcing components.? The probe is similar in concept to the old signal tracers but it is much more sensitive.? I believe he has two versions: one with through-hole and the other using SMT.? He demonstrated the probe on an old receiver that was showing "crackling" noises. and was able to find the bad cap within a few minutes.
Anyway, I scored another victory today: I figured out how to add a 3rd monitor to the shack computer!? More screen area -- yay!
73,
Steve Wedge, W1ES/4
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Saturday, March 9th, 2024 at 1:14 PM, Michael Jensen < kavigal@...> wrote:
Well sorry for the slow reply, work just tend to take up too much of one's spare time ;). Sounds like a very nice trip you and XYL is planning, now I do not travel much these days(I used to), now I just mainly work from home and enjoy monitoring the HF bands, when 'Teams' decides to leave me alone ;).
About that Beer.. Guess I already owe you one, at least as an excuse to get myself one.
Been a few years since I was in Copenhagen, I live in the opposite end of the country all the way up to the North about 50KM south of the most northern point..
And yes we will get to the bottom of this issue, actually I notice something, when I turn on the radio 'ON' to "standby" position the meters consequential "jumps" from ~S9+20 to the S9+40 meter mark, first time I noticed I just though "ohh meter is sticky" but then while troubleshooting I fiddled with the RF gain and guess what? No "sticky" meter when RF gain is fully cranked up quickly.
I noticed twice when "cold" starting the rig, and coinciding "crackling" sound when the meter "jumped", not sure what the right term is in English / U.S.A'ish but same sound a hot 6146B tube can produce just not so pronounced.
It may not be related, just noticed it.. So.. status quo, really eager to get that 12be6 swapped, but the mail man is apparently on vacation in Hawaii current time.
/Michael.
On Thu, Mar 7, 2024 at 6:48?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Yeah, that's a shame that we still have such impediments. In the grand scheme of things, a few 60 year old tubes are nothing. If I was going to Demark this year, I'd pop a couple in my bag and trade them for a beer but we will not be in the area. We will be in HB9, DL, OE, OK, F, G, GW, GM and TF this summer. My XYL is not a ham, so I'm not bringing any radios, unfortunately :-) I mention this in case you're in any of these areas in June or July.
In a couple years, perhaps, we will get to Scandinavia. I worked in Copenhagen for a week long ago and have wanted to tour that area.
We will get to the bottom of this.
73,
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
Sent with secure email.
On Thursday, March 7th, 2024 at 12:26 PM, Michael Jensen < kavigal@...> wrote:
Steve, I'd love the approach of shotgunning, but nope I do not have a complete set.
I do have 2x12ba6 in the mail and 1 12be6 also in the mail, so that will be the starting point.
I did consider and I'd love to get a complete set from K5SVC, but it would add more than 4 times
the money I have in the R4B already, getting tubes from the US to Europe is .. insane..
So thank you to the Danish Government ;)
Anyways, will try the three tube change first, that's kinda where I'm at now.
/Michael
On Thu, Mar 7, 2024 at 5:33?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Now is the time, if you either have a spare set or have another R-4B, to swap every tube out at the same time (¡°shotgunning¡±).
I had an R-4B that was vexing me to no end until I replaced all the tubes and then put swapped the old ones back, one at a time. I found two bad/gassy 12BA6¡¯s and a 12BE6 that passed the tube tester but was no good.
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
On Thu, Mar 7, 2024 at 09:29, Michael Jensen < kavigal@...> wrote: When unpowered, S1+a hair, so very close to zero.
Have checked the following resistors so fare... Just FYI, nothing more.. R9 1.5K** Board 9 OK
R8 220K** Chassis Right Side -R OK
R12 1.5k**Board 9 OK
R13 1.5K**Board 9 OK
R16 1.5K**Board 7 OK
R17 12K* OK
R24 18K* OK
R136 1k** Chassis Left Side -R OK
R142 4.7K**Board 3 OK
R146 22K** Board 3 -- coil OK
/Michael.
On Thu, Mar 7, 2024 at 3:19?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Yes, I have been bit by one of the meter terminals. It hurts :-). This circuit is at around 150V potential.
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
On Thu, Mar 7, 2024 at 01:23, Glenn, OZ1HFT < glenn.mh.dk@...> wrote: Hi Michael
More safety: Let the Drake unlugged power plug and cable be visible to you, on your workbench, while you work on the Drake.
(Then it be much harder to get an accidently electric shock.)
--
best regards,
Glenn, OZ1HFT
|
Re: TR7 with low power on 15 and 10 meter
Been there. Did that. Spot on (slang for absolutely perfect). All my TR7s will get this mod.
73, -Glenn/ WB0DKT
On Wed, Mar 20, 2024 at 10:43?AM Jim Shorney < jimNU0C@...> wrote:
Hi Raoul,
Nice to see you are still at it. You will be better off with the version 2 predriver. 95 Watts on 15m is a good sign. If you have not seen this yet, here is a discussion of the V2 board from the Drakemod paper that may be of interest.
? ? ? ? The? problem? with? the later model board is the bias network on the
? ? ? ? MRF476. Its bias level is such that? the? transistor? will? go? into
? ? ? ? thermal runaway or may latch up by itself. The 270 ohm resistor from
? ? ? ? base? to? ground is not enough to prevent this. The 300 ohm resistor
? ? ? ? and 1N4005 diode is an acceptable method of providing bias, but with
? ? ? ? the grounded emitter, there is no way to guarantee thermal stability
? ? ? ? around the transistor. You'll notice this if all? of? a? sudden? the
? ? ? ? transmitter output drops or, on the lower bands, the ALC is gone and
? ? ? ? more? mic? gain is required. You let up on the mic for a few minutes
? ? ? ? and all is well. If you were to feel the heatsink on the MRF476,? it
? ? ? ? will? be? very, very hot. It may also be possible that the predriver
? ? ? ? board 'eats' MRF476s. You find its bad - usually leaky and low? gain
? ? ? ? - replace it, and soon the new one dies an inglorious death also.
? ? ? ? The? cure? is to lift the emitter off ground with a resistor. Make a
? ? ? ? tight bundle of 3 - 1.8 ohm 1/8 watt resistors in parallel. Cut? the
? ? ? ? emitter? lead? of the MRF476 about where the lead changes width. Re-
? ? ? ? move the stub from the circuit board and put this? resistor? network
? ? ? ? between? the? emitter? and? where the the stub went into the circuit
? ? ? ? board. Removing the stub can be interesting for its soldered on both
? ? ? ? sides of the board.
? ? ? ? Yes, raising the emitter will decrease the? gain.? The? degenerative
? ? ? ? feedback also makes the MRF476 easier to drive, so the net result is
? ? ? ? a? wash.? This one change for this specific board type is highly re-
? ? ? ? commended, especially if you're having problems with MRF476 longev-
? ? ? ? ity.
73
-Jim
NU0C
On Wed, 20 Mar 2024 08:40:30 -0700
"Raoul Meunier" <rmeunier@...> wrote:
> Good morning Jim,
>
> It's been a long time since your last message... My apologies for taking so long to answer you; lots of home distractions here...
> Trying to obtain more power in 10 and 15 meters, I modified the Pre-Driver Version 1 according to the information in DL7MAJ paper ("Full output on 10m").
> The result was good but not enough: 25 Watts on 10 and 95 Watts on 15 meters.?I ended up pulling the Pre-Driver Version 1 and installing a Version 2 one.
> I'll keep on trying to find what's wrong with the Version 1 unit later on...
>
> Best 73 de Raoul CE3RY
>
>
>
>
>
--
73
-Jim
NU0C
|
Re: TR7 with low power on 15 and 10 meter
Hi Raoul, Nice to see you are still at it. You will be better off with the version 2 predriver. 95 Watts on 15m is a good sign. If you have not seen this yet, here is a discussion of the V2 board from the Drakemod paper that may be of interest. The problem with the later model board is the bias network on the MRF476. Its bias level is such that the transistor will go into thermal runaway or may latch up by itself. The 270 ohm resistor from base to ground is not enough to prevent this. The 300 ohm resistor and 1N4005 diode is an acceptable method of providing bias, but with the grounded emitter, there is no way to guarantee thermal stability around the transistor. You'll notice this if all of a sudden the transmitter output drops or, on the lower bands, the ALC is gone and more mic gain is required. You let up on the mic for a few minutes and all is well. If you were to feel the heatsink on the MRF476, it will be very, very hot. It may also be possible that the predriver board 'eats' MRF476s. You find its bad - usually leaky and low gain - replace it, and soon the new one dies an inglorious death also. The cure is to lift the emitter off ground with a resistor. Make a tight bundle of 3 - 1.8 ohm 1/8 watt resistors in parallel. Cut the emitter lead of the MRF476 about where the lead changes width. Re- move the stub from the circuit board and put this resistor network between the emitter and where the the stub went into the circuit board. Removing the stub can be interesting for its soldered on both sides of the board. Yes, raising the emitter will decrease the gain. The degenerative feedback also makes the MRF476 easier to drive, so the net result is a wash. This one change for this specific board type is highly re- commended, especially if you're having problems with MRF476 longev- ity. 73 -Jim NU0C On Wed, 20 Mar 2024 08:40:30 -0700 "Raoul Meunier" <rmeunier@...> wrote: Good morning Jim,
It's been a long time since your last message... My apologies for taking so long to answer you; lots of home distractions here...
Trying to obtain more power in 10 and 15 meters, I modified the Pre-Driver Version 1 according to the information in DL7MAJ paper ("Full output on 10m").
The result was good but not enough: 25 Watts on 10 and 95 Watts on 15 meters.?I ended up pulling the Pre-Driver Version 1 and installing a Version 2 one.
I'll keep on trying to find what's wrong with the Version 1 unit later on...
Best 73 de Raoul CE3RY
-- 73 -Jim NU0C
|
Re: TR7 with low power on 15 and 10 meter
Good morning Jim,
It's been a long time since your last message... My apologies for taking so long to answer you; lots of home distractions here...
Trying to obtain more power in 10 and 15 meters, I modified the Pre-Driver Version 1 according to the information in DL7MAJ paper ("Full output on 10m").
The result was good but not enough: 25 Watts on 10 and 95 Watts on 15 meters.?I ended up pulling the Pre-Driver Version 1 and installing a Version 2 one.
I'll keep on trying to find what's wrong with the Version 1 unit later on...
Best 73 de Raoul CE3RY
|
Re: Soft Rubber Eqp't Feet
3M was the major US manufacturer for Adhesive Rubber Feet.
3M? Bumpon? Protective Products which featured a urethane composition
with a pressure sensitive adhesive.
Bumper Specialties (West Deptford, NJ)
West Florida Components (Tarpon Springs, FL)
Heyco Bumpers and Feet (found with major distributors)
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Re: FW: FW: [cca] wee bit off topic
If the charger is compatible with the number of cells in your battery pack(s) it *should* work. You will want to be careful of charge rates. If the batteries are not rated for fast charge you could damage them if the charger can't be set to a C/10 rate. Also be aware of what is inside your battery packs. If there is a series diode in the path that could throw off the end-of-charge detection. 73 -Jim NU0C On Tue, 19 Mar 2024 19:02:23 -0400 "NU2W" <oemeoc88@...> wrote: I apologize in advance if this offends anyone, but since there are sooo MANY very skilled electronic ops answering lots of tech queries, I thought to take the plunge.
I had a chance to purchase a very SMART battery charger for NiCd and NiMH batts...no Li-Ions.....I thought that since the charger can handle RC devices [cars/planes/hilos] correctly and safely, given those batts heavy duty use and sustainability, that the charger would be fine for HT batts. In fact would this charger be ok with any device using NiMH or NiCd only on the receiving end.
All thoughts appreciated.....AND TU!
STAY SAFE AND STAY WELL!
Respectfully,
Thomas K. Lanieri, NU2W
NJ Licensed EMT; PHTLS, AMLS, PHPEC
B.A.A. EMS Support
ARC N.E. BioMedical Services
ARC N.E. Disaster Health Services
DanaFarber-Am Cancer Society
|
Re: 6JB6 Tube Tester Adapter
I¡¯ll take a 6JB6 PC board
Gary
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Show quoted text
On Mar 19, 2024, at 6:03?PM, Ham Radio <bernard.murphy@...> wrote:
I have 11 of the PCBs in stock for this project. ? Price is $7.00 US including shipping to North America using letter mail service.
--
73, Bernie. VE3FWF
Real?radios glow in the dark
|
Re: 6JB6 Tube Tester Adapter
|
FW: FW: [cca] wee bit off topic
I apologize in advance if this offends anyone, but since there are sooo MANY very skilled electronic ops answering lots of tech queries, I thought to take the plunge.
I had a chance to purchase a very SMART battery charger for NiCd and NiMH batts...no Li-Ions.....I thought that since the charger can handle RC devices [cars/planes/hilos] correctly and safely, given those batts heavy duty use and sustainability, that the charger would be fine for HT batts. In fact would this charger be ok with any device using NiMH or NiCd only on the receiving end.
All thoughts appreciated.....AND TU!
STAY SAFE AND STAY WELL!
Respectfully,
Thomas K. Lanieri, NU2W
NJ Licensed EMT; PHTLS, AMLS, PHPEC
B.A.A. EMS Support
ARC N.E. BioMedical Services
ARC N.E. Disaster Health Services
DanaFarber-Am Cancer Society
|
Re: R-4C Low audio output
Either amp, the original or mine, should clip on a typical signal about 3 or 4 o¡¯clock. ?The IF signal into the protect detector should be about 600 mV P-P above the AGC threshold. If the audio amp can¡¯t clip, suspect the product detector and then the amp.
Rob, NC0B?
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Show quoted text
On Mar 19, 2024, at 4:19?PM, Steve Wedge, W1ES/4 via groups.io <w1es@...> wrote:
?
Either stock or with the Sherwood amp, it should be plenty before 12 o¡¯clock. ?You could have component drift or someone used a different pot.
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
On Tue, Mar 19, 2024 at 1:17 PM, Malcolm G4TJK via groups.io < charlie.porter1@...> wrote:
Thanks for your thoughts! I get audio, but not the level that I¡¯ve had with other examples. The AF gain is at around the 3pm position all of the time.
Vol with headphones is also low-level.
M
|
Re: R-4C Low audio output
Not necessarily. The mod is great if done well. ?I would simply look at how well it was installed.?
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
On Tue, Mar 19, 2024 at 1:19 PM, Malcolm G4TJK via groups.io < charlie.porter1@...> wrote: Steve,
Are you suggesting the removal of the AF mod? Do you have instructions?
Many thank,
Malcolm.
|
Re: R-4C Low audio output
Either stock or with the Sherwood amp, it should be plenty before 12 o¡¯clock. ?You could have component drift or someone used a different pot.
Steve Wedge, W1ES/4
Time flies like an arrow. Fruit flies like a banana.
On Tue, Mar 19, 2024 at 1:17 PM, Malcolm G4TJK via groups.io < charlie.porter1@...> wrote: Thanks for your thoughts! I get audio, but not the level that I¡¯ve had with other examples. The AF gain is at around the 3pm position all of the time.
Vol with headphones is also low-level.
M
|
Re: Soft Rubber Eqp't Feet
This is a perennial topic. Museum putty - or 3M or Gorilla mounting putty works very well.
However, a better solution I've used for many years allows instant moving or changing of the telegraph instrument on the desk.
It is slip-resistant tape, sold my 3M as "Safety Walk" heavy duty anti-slip tread. A small piece of it under each foot of a key will keep it in place. It should be the heavy duty version.
This stuff is designed for walkways around swimming pools and such. Since it's thin it won't raise the key very much. Other brands probably will be inferior.
My local Ace Hardware sells it in a roll, by the foot, so I buy one foot 3 or 4 inches wide, good for dozens of keys. If you mail order it the price for a 60 foot roll is about $45.
Pete
WB2QLL
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Show quoted text
-----Original Message----- From: < [email protected]> Sent: Mar 17, 2024 2:32 PM To: < [email protected]> Subject: Re: [DRAKE-RADIO] Soft Rubber Eqp't Feet Okay, apparently a lot of people are unfamiliar with the undercarriage on Vibroplex keys :-) See the 1st picture attached. From L-R those are the bottom sides of an Iambic, a Vibrokeyer, and a standard bug. There's a lot of stuff going on under there. Double sided tape, gluing on rubber sheets, etc., aren't an option. (And though it probaly won't work here, either, "museum putty" sounds very cool and deserves further exploration. It could be useful for keeping things like watt meters from wandering about.) At the bottom of the 1st pic is the butt side of the road warrior key I put together. Those stick-on bumpers stick like glue! If I could find a taller version of those, I could just remove the feet from all the keys and replace them with the bumpers. I did come up with a workaround for the main offender, though. (See 2nd picture attached.) I found some small stick-on bumpers I had forgotten about. These keep the key nicely stuck to the desk, but they elevate it to where the finger pieces are higher up than I like. It will work for now, but it's not a long term solution. Anyway, still searching ... :-) --lyndon
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Re: R-4C Low audio output
Working as it did before the change¡.
M
|
Jim Shorney
Greg W9GB
Ham Radio
NU2W
Rob Sherwood