Modifications

2020-06-06T00:16:15Z

VE3CFK: /* Modifications */

Modifications

2020-06-06T00:15:23Z

VE3CFK:

Plan Execution

2020-06-05T12:46:43Z

VE3CFK:

Work began on February 10, 2020.
[[File:30S1 Working Diary.jpg|536px|thumb|right|A copy of the 30S1 manual, Eimac 4CX1000A spec sheets and miscellaneous notes stored under various tabs]]
A working diary was maintained throughout the rebuild. This serves as a visual and written confirmation that something was done as opposed to using ones memory. Additionally it is a convenient place to store photos, schematics and other notes pertaining to the build. Most importantly it is a place to create "Things to remember to do". Such as "retightening ALL HV connections before turning power on". There were times during the rebuild where it was necessary to disconnect something in the HV circuit. I didn't want to forget to reconnect and tighten, so a deliberate note was made on the "Things to re..." page.

Another invaluable "checklist" item was a copy of the complete schematic.

[[File:30S1 Schematic.jpg|500px|thumb|left]]

Each component of the amplifier was checked for conformance with the Collins specification, and if found to be out of tolerance, was replaced. I used a tighter tolerance than Collins specified. For example if the specification for a resistor was 10%, I made sure it was 5% or better. Each component on the schematic was color coded. GREEN for checked and OK as is, YELLOW denoted that Bob had replaced the component and was validated as OK and BLUE denoted that it was replaced by myself because it was out of specification, looked compromised or just wasn't shiny enough.

All told there were 58 components replaced by myself and 8 replaced by Bob.
Bob had actually replaced more than 8 components. Some electrolytics he had replaced were possibly 18 years old. Although they may have never seen voltage, I automatically assumed that they needed replacement. It's my philosophy towards electrolytics. If they are older than 10 years old. Replace them. The cheap no-name electrolytics you find on eBay come from less than reputable sources and are not of the quality of Vishay or Phillips. So if in doubt, replace.

Some of the major components replaced were relays, step-start resistors, bleeder resisters, filament adjust potentiometer, the SSB/CW switch and the 4CX1000A. Fortunately all the transformers and chokes were okay as received. I could not tell whether they were originals, replacements, or originals that were repainted. In the final analysis it really did not matter. They all worked.

To facilitate access to the lower cabinet where the relay shelf and HV components were located, I placed the amplifier atop a rolling file cabinet. This allowed non yoga positions to get way back into the back of the cabinet, it also provided storage of 30S1 parts.

[[File:Where did washer go.jpg|250px|thumb|right|Oh it's gonna be a bugger turning this thing upside down and shaking it to get that washer out!]]
One item that was extensively reconditioned was the cooling system. The motor and fan were filthy. They were completely cleaned and degreassed. I went further and replaced the stock motor with a 3000 RPM motor replacing the stock 1500 RPM motor. Also installed was an electronic variable speed controller with override switch. See photo below.

[[File:30S1 speed control.jpg|500px|thumb|center]]

These were mounted in an inconspicuous spot that would only be noticeable if you got down on your hands and knees but also located so that the operator could quickly open the main cabinet door, flip a switch and achieve the desire flow condition. Plus it was mounted in such a manor that the Collins aficionado would have to really go out of his way to find the two holes that were put in the chassis.

Each sub-system was individually validated. For example. The 180 second cathode warm-up interlock circuit was validated by disconnecting and replacing the +12 VDC source with an external fused +12VDC power supply and powered up. If the circuit did not energize the required relay, well, there was more trouble shooting to do. The HV supply, the bias supply, the screen voltage supply, the antenna changeover circuitry, the metering circuitry, etc. were all independently validated. This made trouble shooting the integrated system easier knowing where the fault was NOT located.

One of the most challenging tasks was restringing the band switch. This singular task took 3 hours. I wondered what Art was thinking when he incorporated this treacherous method of simultaneously switching 2 switches? While I was cursing him out for being cheap, it dawned on me that it really was a cost effective way of accomplishing what needed to be done. Since the display panel is on an angle relative to the chassis front panel, implementing a gearing mechanism to accomplish the same task as using fishing line would have doubled the cost of the 30S1. So I let Art off the hook on this one!

''Click on the bold type to move to next page''.
== [[Moment(s) of Truth]] ==

Completed Collins 30S-1

2020-06-04T00:05:06Z

VE3CFK:

Well. I wasn't far off on my estimate in the amount of time it would take to rebuild my bushel basket project. Original estimate was a total of 240 hours. The final figure came in at 220 hours. Not bad +-8%

Here are some pics of the completed project:

[[File:30S1 front view.jpg|520px|thumb|left|Parts, Parts]]

Completed Collins 30S-1

2020-06-04T00:04:12Z

VE3CFK:

Well. I wasn't far off on my estimate in the amount of time it would take to rebuild my bushel basket project. Original estimate was a total of 240 hours. The final figure came in at 220 hours. Not bad +-8%

Here are some pics of the completed project:

[[File:30S1 Parts1.jpg|520px|thumb|left|Parts, Parts]]

2020-05-30T00:49:31Z

VE3CFK:

Modifications

2020-05-29T19:28:26Z

VE3CFK:

What? Modify a Collins? If it needed modification, Art Collins would have already incorporated the modification.

Well maybe. Art didn't live in the new millennium.

Art intentionally made the 30S-1 cabinet large with lots of space so that ardent amateur radio operators could make enhancements to his design that he would be proud of. I'm sure.

He didn't include 160M into the 30S-1 because the KWM-1 did not have 160M and neither did the KWM-2. The 30S-1 was to be the companion to these two transceivers. Since they did not have 160M, why include it in the 30S-1? But he left plenty of room to include 160M as proven by Chris, KB3BF.

The following are the intentional modifications I incorporated into the rebuild:

1. Rewired the dial lighting so that the dial lights would turn on only after the 180 second cathode warm up cycle had timed out. This is convenient, knowing when you could apply the HV to the amplifier, but also aided in trouble shooting the circuitry should the occasion require it.

2. Replaced the stock 1500 RPM fan motor with a 3000 RPM motor complete with electronic speed control and bypass switch.

3. Replaced stock 4CX1000A tube with 4CX1500B tube.

4. Installed screen boost transformer to raise screen voltage from 200 VDC to 325 VDC.

5. Increased the voltage rating of C-204 to accommodate the increase in screen voltage.

6. Replaced stock RCA RF Input connector with N-type RF connector.

7. Replaced K-203 with a robust 4PST contactor. It will never fail!

8. Replaced 3B28 rectifiers with solid state equivalents.

9. Converting the HV supply to 3kV for CW operation.

All modifications, with exception of number 6, can be uninstalled to original factory condition. I intentionally did number 6 because of an unfortunate experience in 1970 with a failed RCA connector carrying 100 watts of RF. The result was a couple of 6146s that were destroyed. Using substandard connectors in RF circuitry cannot be excused. I'm sorry.

== Future Modifications? ==

1. Replace all the incandescent bulbs with LED equivalents.

2. Installing 160M capability

3. Peter Dahl replacement of T-201

Moment(s) of Truth

2020-05-29T01:06:47Z

VE3CFK:

Working, restoring, rebuilding, checking, validating all seem to be enjoyable. Each step of the process is thought out and the expected result is a function of ones skills in performing each step. But turning on the power. Well. For some reason the adrenaline increases. The heart rate goes up. One stands back from the open enclosure to prevent personal injury should there be a flash over.

But nothing happened other than the metering lights illuminated. After 180 seconds the dial lights illuminated indicating that the prerequisite time to warm up the 4CX1000A cathode has elapsed and it is now OK to turn on the high voltage. Check the filament voltage and it is 6+ VAC (since no tube has been installed at this point). Check the bias voltage and it was adjusted to -80 VDC. All other readings of the multi meter are zero. So far so good.

Now. Turn on the high voltage. Again. Nothing happens except the Red HV lamp comes on! Check the HV reading and it indicates +3200 volts.

The heart rate starts to return to normal. I reach for a cold one. That Coke sure did go down smooth!

So the next step is to install a tube. The original 4CX1000A was installed. Turned on the power and then the HV. Set the filament voltage to the requisite 6 VAC. All meter readings read nominal. Key the amplifier. Still NO smoke or noises. Adjust the idle plate current to 200 mA. Plate voltage drops to 2800 VDC. All readings nominal except grid current. When the amplifier is keyed with no RF, there is a small amount of negative grid current. This 4CX1000A is destined for the scrap heap.

Installed my spare (looks new) 4CX1000A. Again all multi meter readings nominal and there is NO discernible grid current with this tube. On to the next step. Introduce some RF into the 30S-1 and lets see what kind of rebuild we mustered.

Well. Well. Well. Lookie see. 30 watts of drive and 700 watts output. Just like the original specification in the Collins 30S-1 operating manual. I guess we did alright with our rebuild. This one is for you Bob.

BUT. The story does not end here.

Next we replaced the 4CX1000A tube with a 4CX1500B tube. Result? 30 watts input and 950 watts output. Things just keep on getting better.

BUT. The story does not end here either.

Next we installed the screen boost transformer that came with my bushel basket project. This boosts the screen voltage from 200 VDC to 325 VDC. Result? 1500 watts output!

''Click on the bold type to move to next page.''
== [[Modifications]] ==

Main Page

2020-05-27T23:14:06Z

VE3CFK: Reverted edits by VE3CFK (talk) to last revision by Gordonp

{| border="1" cellpadding="6" cellspacing="0" style="border: black solid 1px; border-collapse: collapse; text-align: left; width: 100%; background: #f0f0ff; "
| colspan="3" style="text-align: center; font-weight: bold; font-size: 1.4em;" |
<strong>Information, Repairs, Upgrades and Notes for Collins 30S-1 HF Amplifier</strong>
|-
| width="33%" valign="top" | '''Gord - VA7GP'''
* [[Acquisition]]
* [[Repair]]
* [[Operation]]

| width="33%" valign="top" | '''Chris - KB3BF'''
* [[160m Mods]]

| width="33%" valign="top" | '''Chet - VE3CFK'''
* [[The Acqusition]]
* [[The Game Plan]]
* [[Plan Execution]]
* [[Moment(s) of Truth]]
* [[Modifications]]
* [[Completed Collins 30S-1]]

|}

[[File:30s1_frontview.jpeg|500px|thumb|center]]

Main Page

2020-05-27T23:13:48Z

VE3CFK:

{| border="1" cellpadding="6" cellspacing="0" style="border: black solid 1px; border-collapse: collapse; text-align: left; width: 100%; background: #f0f0ff; "
| colspan="3" style="text-align: center; font-weight: bold; font-size: 1.4em;" |
<strong>Information, Repairs, Upgrades and Notes for Collins 30S-1 HF Amplifier</strong>
|-
| width="33%" valign="top" | '''Gord - VA7GP'''
* [[Acquisition]]
* [[Repair]]
* [[Operation]]

| width="33%" valign="top" | '''Chris - KB3BF'''
* [[160m Mods]]

| width="33%" valign="top" | '''Chet - VE3CFK'''
* [[Basket Case Purchase]]
* [[The Game Plan]]
* [[Plan Execution]]
* [[Moment(s) of Truth]]
* [[Modifications]]
* [[Completed Collins 30S-1]]

|}

[[File:30s1_frontview.jpeg|500px|thumb|center]]

2020-05-24T16:45:12Z

VE3CFK:

The Collins 30S-1 was acquired from the estate of Bob, K8VFV who became a silent key in 2018.
The amplifier was a basket case, actually a bushel basket case. There was the main RF cabinet and power supply cabinet and 4 additional boxes containing the parts that at one time were inside the 30S-1 enclosure.

[[File:30S1 Parts1.jpg|520px|thumb|left|Parts, Parts]]

[[File:30s1 parts2.jpg|536px|thumb|right|and more parts. Many of the parts in plastic bags were new parts Bob had purchased that were to replace the original parts within the 30S1]]

Bob had been restoring the amplifier since his acquisition in 2001. He had stripped many components from the chassis and cabinet during his restoration process. He had the cabinet professionally powder coated to the original Collins colors. The cabinet as received, was immaculate as if it had just come out of the Cedar Rapids, IA manufacturing plant.

Many components in the power supply appeared to be brand new. But upon closer examination, it appears that Bob had removed the HV capacitors and HV choke and other components and had them repainted professionally as well. Even the HV capacitor hold down brackets were repainted.

The story goes that this particular amplifier came from merchant marine service. Probably a salty one. There are noticeable signs of galvanic corrosion. Most significant was between the chassis and the copper finger grounding straps on the top lid. The copper fingers were replaced with newer original fingers by Bob.

It was obvious that Bob had planned on doing a very professional restoration of the Collins 30S-1 that would rank a CCA of at least 9.5

Click on the bold type to move to next page.

== [[The Game Plan]] ==

The Acqusition

2020-05-24T16:43:25Z

VE3CFK:

The Collins 30S-1 was acquired from the estate of Bob, K8VFV who became a silent key in 2018.
The amplifier was a basket case, actually a bushel basket case. There was the main RF cabinet and power supply cabinet and 4 additional boxes containing the parts that at one time were inside the 30S-1 enclosure.

[[File:30S1 Parts1.jpg|520px|thumb|left|Parts, Parts]]

[[File:30s1 parts2.jpg|536px|thumb|right|and more parts. Many of the parts in plastic bags were new parts Bob had purchased that were to replace the original parts within the 30S1]]

Bob had been restoring the amplifier since his acquisition in 2001. He had stripped many components from the chassis and cabinet during his restoration process. He had the cabinet professionally powder coated to the original Collins colors. The cabinet as received, was immaculate as if it had just come out of the Cedar Rapids, IA manufacturing plant.

Many components in the power supply appeared to be brand new. But upon closer examination, it appears that Bob had removed the HV capacitors and HV choke and other components and had them repainted professionally as well. Even the HV capacitor hold down brackets were repainted.

The story goes that this particular amplifier came from merchant marine service. Probably a salty one. There are noticeable signs of galvanic corrosion. Most significant was between the chassis and the copper finger grounding straps on the top lid. The copper fingers were replaced with newer original fingers by Bob.

It was obvious that Bob had planned on doing a very professional restoration of the Collins 30S-1 that would rank a CCA of at least 9.5

Click on the bold type to move to nest page.
[['''The Game Plan''']]

The Acqusition

2020-05-24T16:42:08Z

VE3CFK: