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Reviews For: Heathkit HW-99

Category: Transceivers: HF Amateur HF+6M+VHF+UHF models - non QRP <5W

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Review Summary For : Heathkit HW-99
Reviews: 3MSRP: 299.95
Description:
Four Band (80-40-15-10 Meter) 50-watt CW-only transceiver, offered in kit form from 1985-1986, had built-in power supply for 120 VAC
Product is not in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0033.3
K3JLS Rating: 2023-10-08
Works Acceptably - After Some Tweaking Time Owned: 0 to 3 months.
I bought this radio mainly because a friend of mine bought one new, assembled it and took it back to the Heathkit store for countless repairs (kept blowing the final).
Anyway - it was a quest for a nice bedside rig. It was assembled very nicely and in great cosmetic condition. It came with an assembly manual less schematics. And yes, it drifted somewhat.

I checked W9RAS' (very nice guy) suggestions and spoke with him on the phone. I opened up the VFO can (after removing the oscillator board) and noticed that the VFO coil has shellacked (good thing) and is not epoxied.

I also cross checked the value of the capacitors - they were the proper NPO units shown in the assembly manual and the same values used in other successful Heathkit VFO designs so I left them alone.

I did note that the VFO was very sensitive when the coil shield was touched even with a non conductive item like plastic alignment wand. This is because the shield would move - perhaps ever so slightly - as the radio warmed up and during transmissions. To remedy this flexing I pressed the shield firmly in place when re-soldering it. I also ran a ground lead to a nearby board mounting screw.

I did not paint the inside of the can nor build a thermal insulator for it.

There was another problem with the BFO as the oscillator was drifting ever so slightly. I replaced the MPF-105 with an MPF-102 and this solved this problem. I don't know if I had a bad MFP-105 or if there was something wrong with the initial design, but the new transistor fixed it.

I should have mentioned that I loosened and re-tightened all the board mounting screws (good practice when troubleshooting older rigs as intermittent ground connections can be very hard to locate).

One final point. If you look at the schematic you'll note that C266 is tied the VFO oscillator and diode switched in (D221) during the RECEIVE mode. This is a frequency determining component - used to provide the proper offset when transmitting. It also could have been contributing to the drift. I wanted to replace it while I had the board out but didn't have a suitable NPO equivalent. Anyway - time will tell.

All-in-all, a fun rig - not bad for Heath's Swan Song!
N8RS Rating: 2014-07-20
LAST HEATHKIT NOVICE RIG Time Owned: 3 to 6 months.
I left my job in Heathkit engineering when the layoffs were coming thick and fast this was when the HW-99 was being designed . Never having a chance to even examine one while I was at Heath I jumped at the chance to buy one on Ebay that was assembled but had not been aligned and did not work . I found much of the HW-99 to be similar to the QRP rig the HW-9. A complete alignment and repairing shorted coil T-201 got things working .Alignment is somewhat confusing as listed in the manual and use of a well equipped work bench with frequency counter,scope,signal generator etc. made it easier . The CW delay was found to be much to short for my taste in my opinion a "Novice " rig should have longer delay to allow for very slow CW speeds. The continual switching from transmit to receive was annoying to me . So the first mod was to change capacitor C-283 located by the CW delay control from 22 UF to 47 UF this increased CW delay considerably for very slow CW.
Another annoying thing was rather bad VFO drift . Taking the VFO can off revealed that the VFO coil 40-2111 was the trouble making coil coated with Epoxy . The older style coil coated with Shellac is much more stable I could not find a replacement coil with the shellac coating . The first thing done was to bake the rig at 170 degrees in the kitchen oven VERY CAREFULLY using a second thermometer in the oven to be sure 170 degrees was not exceeded. After baking the VFO frequency had changed quite a bit about 30 khz due to removal of moisture etc. The drift was less now but still excessive . The VFO can was now painted inside with flat black paint from the craft store and the outside of the VFO can was covered by two layers of metal aluminum tape sold at hardware stores for taping furnace ducts .Changing the capacitors on the VFO oscillator to the same as the SB-104 got the VFO working very stable . Adding a second 6 pf N470 cap to ground in parallel with the one in the SB-104 circuit and the VFO now settles down and is very stable after about a 10 minute warm up . The Sb-104 parts used are as follows 2-510 Pf N750,1-510 Pf N1500 ,1-56 PF N75 , 1-6pf N470 . A second 6 PF N470 was added when the vfo showed very slight drift . Placement of these parts can be seen on the SB-104 schematic . Stability now is very good and a long rag chew CW session can be done with no discernible drift . The HW-99 after alignment,repair and getting the VFO to run stable
is a joy to use . No extra controls , No fancy bells and whistles just tune in a guy and start pounding the brass its that easy .Summing up about the VFO The dial could not be aligned to be accurate when I first got the rig working and is even less accurate after the VFO was modified to match the one in the SB-104 but it is now very stable which to me is much more important . Either case I highly recommend you have some way to insure you are operating properly IN the amateur radio bands a external 100KHZ calibrator would help or a frequency counter or a good receiver to check with . On this HW-99 I carefully adjusted the VFO on 40 meters so 7.000 MHZ was right on the 7.000 mark on the dial this way I Know I am operating IN the Band . The power output on THIS HW-99 exceeds specifications by a huge margin on 80 and 40 an output of 80 watts out was observed on the calibrated Bird wattmeter . For this reason I recommend use of a quiet cooling fan blowing on the heat sink and an inline wattmeter so you can set the output to 50 watts or less and no more to avoid burning out the final transistor that is actually rated by the manufacturer at 40 watts !


I hope all my rambling here is not to confusing .



Overall I give the HW-99 a good rating because AFTER all the time aligning and repairing the rig is a real joy to operate . I recommend it as a rig for a CW beginner and old timer alike AFTER it is properly aligned and working properly . It is a rare Heathkit produced as the company was going out of business.

This HW-99 is on youtube in a video just search on youtube for HW-99 .

73 and good DX Bob W9RAS
N7EKX Rating: 2005-01-23
Shaky at Best Time Owned: more than 12 months.
I purchased this rig at a flea market, from a gentleman that assured me everything worked fine. Because of my great love for Heathkits (and some Navy experience in electronic repair), I paid him the $150 in 1996, and took the rig home, only to find it didn't transmit or receive on any band! After replacing countless parts, and performing numerous alignments, the power supply exploded as a grand finale to my efforts. Not to admit defeat, I quickly rebuilt the power supply with upgraded diodes, and eagerly put my newly rebuilt HW-99 on the air. Imagine my disappointment when the rig drifted so badly that normal QSO's were almost impossible! Upon investigation, I found out that this serious drift is a design problem in the rig, and Heath's own specs admit that it drifts badly! Around the time of production, Heath's amateur radio division was really on the ropes, and this product apparently got sold with a poor VFO design. I feel embarassed to use it on the air, except for hit-and-run contest contacts, when the drift isn't so noticeable. Even if you warm it up for 90 minutes before usage, the VFO will still start serious drift because of the heat radiated from the heat shield. If any readers know of a solution to the drift problem, no matter how technical, I would certainly appreciate an E-mail.